diff --git a/src/components/AdvancedEventLab/AdvancedEventLabDialog.tsx b/src/components/AdvancedEventLab/AdvancedEventLabDialog.tsx
index 1eb69f99..beaefaff 100644
--- a/src/components/AdvancedEventLab/AdvancedEventLabDialog.tsx
+++ b/src/components/AdvancedEventLab/AdvancedEventLabDialog.tsx
@@ -17,12 +17,15 @@ import {
 import logger from '@/lib/logger'
 import { isLanguageToolConfigured } from '@/lib/languagetool-client'
 import { languageToolLintExtension, requestAdvancedLabGrammarLint } from '@/lib/languagetool-cm-linter'
-import { buildLanguageToolPreferenceList } from '@/lib/languagetool-language-order'
+import {
+  buildLanguageToolPreferenceList,
+  pickLanguageToolCodeForTranslateTarget
+} from '@/lib/languagetool-language-order'
 import type { AdvancedEventLabSlice } from '@/lib/advanced-event-lab-slice'
+import { translateAdvancedLabMarkup } from '@/lib/advanced-lab-markup-protect'
 import {
   fetchTranslateLanguages,
   isTranslateConfigured,
-  translatePlainText,
   type TranslateLanguageOption
 } from '@/lib/translate-client'
 import { setReadAloudTranslationForEvent } from '@/lib/read-aloud-translation-override'
@@ -43,10 +46,13 @@ import { useCallback, useEffect, useLayoutEffect, useMemo, useRef, useState } fr
 import { useTranslation } from 'react-i18next'
 import { toast } from 'sonner'
 import { AdvancedEventLabMarkupToolbar } from './AdvancedEventLabMarkupToolbar'
+import { AdvancedEventLabPreviewPane } from './AdvancedEventLabPreviewPane'
 import customEmojiService from '@/services/custom-emoji.service'
 import postEditorCache from '@/services/post-editor-cache.service'
 import type { TEmoji } from '@/types'
 
+const PREVIEW_DEBOUNCE_MS = 200
+
 /** Subset of {@link TPostTextareaHandle} so media upload + toolbar can target the lab surface. */
 export type AdvancedLabBodyHandle = {
   getText: () => string
@@ -99,6 +105,10 @@ export type AdvancedEventLabDialogProps = {
    * clears this draft so the next open is seeded from TipTap again.
    */
   draftPersistenceKey?: string | null
+  /** Lab preview: resolve custom `:shortcode:` from this author's NIP-30 inventory when tags do not define them. */
+  previewAuthorPubkey?: string | null
+  /** Lab preview: `emoji` tags on the fake event (e.g. copied from the event being edited). */
+  previewEmojiTags?: string[][]
 }
 
 function useDarkModeFlag(): boolean {
@@ -129,7 +139,9 @@ export default function AdvancedEventLabDialog({
   onApply,
   bodyApiRef,
   formatToolbar,
-  draftPersistenceKey = null
+  draftPersistenceKey = null,
+  previewAuthorPubkey = null,
+  previewEmojiTags
 }: AdvancedEventLabDialogProps) {
   const { t, i18n } = useTranslation()
   const dark = useDarkModeFlag()
@@ -138,11 +150,45 @@ export default function AdvancedEventLabDialog({
   const sliceRef = useRef<AdvancedEventLabSlice | null>(null)
   const draftPersistenceKeyRef = useRef<string | null>(null)
   const labPersistTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const previewDebounceTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const schedulePreviewUpdateRef = useRef<(text: string) => void>(() => {})
   /** When true, closing is from Apply (draft already cleared); skip discard cleanup. */
   const skipClearLabDraftOnCloseRef = useRef(false)
   /** Debounce writes to the draft map; pagehide/beforeunload flush immediately to disk. */
   const LAB_DRAFT_DEBOUNCE_MS = 500
 
+  const [previewDoc, setPreviewDoc] = useState('')
+
+  const mergedLabPreviewEmojiTags = useMemo(() => {
+    if (!open || !initial) return []
+    const fromInitial = initial.tags.filter(([n]) => n === 'emoji').map((r) => [...r])
+    const fromProp = previewEmojiTags ?? []
+    const m = new Map<string, string[]>()
+    for (const row of fromInitial) {
+      const sc = row[1]?.trim()
+      if (sc) m.set(sc.toLowerCase(), row)
+    }
+    for (const row of fromProp) {
+      const sc = row[1]?.trim()
+      if (sc) m.set(sc.toLowerCase(), row)
+    }
+    return [...m.values()]
+  }, [open, initial, previewEmojiTags])
+
+  const schedulePreviewUpdate = useCallback((text: string) => {
+    if (previewDebounceTimerRef.current) {
+      clearTimeout(previewDebounceTimerRef.current)
+    }
+    previewDebounceTimerRef.current = setTimeout(() => {
+      previewDebounceTimerRef.current = null
+      setPreviewDoc(text)
+    }, PREVIEW_DEBOUNCE_MS)
+  }, [])
+
+  useEffect(() => {
+    schedulePreviewUpdateRef.current = schedulePreviewUpdate
+  }, [schedulePreviewUpdate])
+
   draftPersistenceKeyRef.current = draftPersistenceKey ?? null
 
   const flushLabDraftNow = useCallback((key: string) => {
@@ -180,6 +226,16 @@ export default function AdvancedEventLabDialog({
     }
   }, [open, draftPersistenceKey, flushLabDraftNow])
 
+  useEffect(() => {
+    if (!open) {
+      if (previewDebounceTimerRef.current) {
+        clearTimeout(previewDebounceTimerRef.current)
+        previewDebounceTimerRef.current = null
+      }
+      setPreviewDoc('')
+    }
+  }, [open])
+
   const handleDialogOpenChange = useCallback(
     (next: boolean) => {
       if (!next) {
@@ -311,6 +367,7 @@ export default function AdvancedEventLabDialog({
         tags: initial.tags.map((row) => [...row])
       }
       sliceRef.current = baseSlice
+      setPreviewDoc(baseSlice.content)
 
       const markupLang: Extension =
         markupMode === 'asciidoc' ? StreamLanguage.define(asciidoc) : markdown()
@@ -331,7 +388,7 @@ export default function AdvancedEventLabDialog({
           '&': { maxHeight: '100%' },
           '.cm-scroller': { overflow: 'auto' },
           '.cm-content': {
-            minHeight: 'min(50dvh, 42rem)',
+            minHeight: 'min(22dvh, 11rem)',
             fontFamily: 'var(--font-mono, ui-monospace, monospace)'
           }
         }),
@@ -341,11 +398,14 @@ export default function AdvancedEventLabDialog({
           const s = sliceRef.current
           if (!s) return
           s.content = content
+          schedulePreviewUpdateRef.current(content)
           scheduleLabDraftPersist()
         })
       ]
       if (isLanguageToolConfigured()) {
-        mkExtensions.push(languageToolLintExtension(() => ltLangRef.current, 650))
+        mkExtensions.push(
+          languageToolLintExtension(() => ltLangRef.current, 650, () => markupMode)
+        )
       }
       if (dark) mkExtensions.push(oneDark)
 
@@ -402,6 +462,10 @@ export default function AdvancedEventLabDialog({
     return () => {
       cancelled = true
       cancelAnimationFrame(rafId)
+      if (previewDebounceTimerRef.current) {
+        clearTimeout(previewDebounceTimerRef.current)
+        previewDebounceTimerRef.current = null
+      }
       if (labPersistTimerRef.current) {
         clearTimeout(labPersistTimerRef.current)
         labPersistTimerRef.current = null
@@ -463,13 +527,24 @@ export default function AdvancedEventLabDialog({
       inputChars: text.length
     })
     try {
-      const out = await translatePlainText(text, translateTarget, translateSource)
+      const out = await translateAdvancedLabMarkup(text, translateTarget, translateSource, markupMode)
       if (!markupView.current) return
       markupView.current.dispatch({
         changes: { from: 0, to: markupView.current.state.doc.length, insert: out }
       })
       const s = sliceRef.current
       if (s) s.content = out
+      if (isLanguageToolConfigured()) {
+        const nextLt = pickLanguageToolCodeForTranslateTarget(translateTarget, ltList)
+        if (nextLt !== ltLang) {
+          logger.info('[AdvancedLab] grammar language synced after translate', {
+            from: ltLang,
+            to: nextLt,
+            translateTarget
+          })
+          setLtLang(nextLt)
+        }
+      }
       toast.success(t('Advanced lab translate done'))
     } catch (e) {
       toast.error(e instanceof Error ? e.message : String(e))
@@ -606,18 +681,33 @@ export default function AdvancedEventLabDialog({
 
         <AdvancedEventLabMarkupToolbar markupMode={markupMode} viewRef={markupView} sliceRef={sliceRef} />
 
-        <div className="flex-1 min-h-0 flex flex-col gap-1 px-4 py-2 overflow-hidden">
-          <span className="text-xs font-medium text-muted-foreground shrink-0">
-            {t(
-              markupMode === 'asciidoc'
-                ? 'Advanced lab markup label asciidoc'
-                : 'Advanced lab markup label markdown'
-            )}
-          </span>
-          <div
-            ref={markupHost}
-            className="flex-1 min-h-[min(50dvh,36rem)] border rounded-md overflow-hidden bg-muted/20"
-          />
+        <div className="flex-1 min-h-0 flex flex-col gap-3 px-4 py-2 overflow-hidden lg:flex-row lg:gap-0">
+          <div className="flex flex-1 min-h-0 min-w-0 flex-col gap-1 lg:pr-3">
+            <span className="text-xs font-medium text-muted-foreground shrink-0">
+              {t(
+                markupMode === 'asciidoc'
+                  ? 'Advanced lab markup label asciidoc'
+                  : 'Advanced lab markup label markdown'
+              )}
+            </span>
+            <div
+              ref={markupHost}
+              className="flex-1 min-h-[min(28dvh,14rem)] lg:min-h-[min(42dvh,24rem)] border rounded-md overflow-hidden bg-muted/20"
+            />
+          </div>
+          <div className="flex flex-1 min-h-0 min-w-0 flex-col gap-1 border-t border-border pt-3 lg:flex-[0_1_42%] lg:max-w-[min(50%,40rem)] lg:border-l lg:border-t-0 lg:pl-3 lg:pt-0">
+            <span className="text-xs font-medium text-muted-foreground shrink-0">
+              {t('Advanced lab preview')}
+            </span>
+            <div className="flex-1 min-h-[min(24dvh,12rem)] lg:min-h-0 overflow-y-auto rounded-md border bg-muted/10 px-2 py-2">
+              <AdvancedEventLabPreviewPane
+                markupMode={markupMode}
+                source={previewDoc}
+                previewAuthorPubkey={previewAuthorPubkey}
+                previewEmojiTags={mergedLabPreviewEmojiTags}
+              />
+            </div>
+          </div>
         </div>
 
         {formatToolbar ? (
diff --git a/src/components/AdvancedEventLab/AdvancedEventLabPreviewPane.tsx b/src/components/AdvancedEventLab/AdvancedEventLabPreviewPane.tsx
new file mode 100644
index 00000000..4fc19e04
--- /dev/null
+++ b/src/components/AdvancedEventLab/AdvancedEventLabPreviewPane.tsx
@@ -0,0 +1,55 @@
+import AsciidocArticle from '@/components/Note/AsciidocArticle/AsciidocArticle'
+import MarkdownArticle from '@/components/Note/MarkdownArticle/MarkdownArticle'
+import { Card } from '@/components/ui/card'
+import { ExtendedKind } from '@/constants'
+import { createFakeEvent } from '@/lib/event'
+import { kinds } from 'nostr-tools'
+import { memo, useMemo } from 'react'
+import { useTranslation } from 'react-i18next'
+
+export const AdvancedEventLabPreviewPane = memo(function AdvancedEventLabPreviewPane({
+  markupMode,
+  source,
+  previewAuthorPubkey = null,
+  previewEmojiTags
+}: {
+  markupMode: 'markdown' | 'asciidoc'
+  source: string
+  /** When set (hex pubkey), Markdown preview resolves custom `:shortcode:` from this author (NIP-30). */
+  previewAuthorPubkey?: string | null
+  /** `emoji` tags on the preview fake event (e.g. from the note being edited). */
+  previewEmojiTags?: string[][]
+}) {
+  const { t } = useTranslation()
+
+  const fakeEvent = useMemo(() => {
+    const kind =
+      markupMode === 'asciidoc' ? ExtendedKind.WIKI_ARTICLE : kinds.LongFormArticle
+    const pk = (previewAuthorPubkey ?? '').trim().toLowerCase()
+    const tags = (previewEmojiTags ?? []).map((row) => [...row])
+    return createFakeEvent({
+      content: source,
+      kind,
+      tags,
+      pubkey: pk
+    })
+  }, [markupMode, source, previewAuthorPubkey, previewEmojiTags])
+
+  if (!source.trim()) {
+    return (
+      <p className="text-sm text-muted-foreground px-1 py-2">{t('Advanced lab preview empty')}</p>
+    )
+  }
+
+  return (
+    <Card className="border-0 bg-transparent p-0 shadow-none">
+      <div className="select-text max-w-none text-sm">
+        {markupMode === 'asciidoc' ? (
+          <AsciidocArticle event={fakeEvent} hideImagesAndInfo={false} />
+        ) : (
+          <MarkdownArticle event={fakeEvent} hideMetadata lazyMedia={false} />
+        )}
+      </div>
+    </Card>
+  )
+})
diff --git a/src/components/ContentPreview/Content.tsx b/src/components/ContentPreview/Content.tsx
index 8c0adef7..2e6c24e5 100644
--- a/src/components/ContentPreview/Content.tsx
+++ b/src/components/ContentPreview/Content.tsx
@@ -7,7 +7,7 @@ import { useMemo } from 'react'
 import { useTranslation } from 'react-i18next'
 import PaytoLink from '../PaytoLink'
 import { EmbeddedMentionText } from '../Embedded'
-import Emoji from '../Emoji'
+import Emoji, { EMOJI_IMG_INLINE_CLASS } from '../Emoji'
 
 export default function Content({
   content,
@@ -52,9 +52,10 @@ export default function Content({
         if (node.type === 'emoji') {
           const shortcode = node.data.slice(1, -1).trim()
           const emoji = emojiInfos?.find((e) => e.shortcode === shortcode)
-          if (emoji) return <Emoji key={index} emoji={emoji} classNames={{ img: 'size-4' }} />
+          if (emoji) return <Emoji key={index} emoji={emoji} classNames={{ img: EMOJI_IMG_INLINE_CLASS }} />
           const native = shortcodeToEmoji(shortcode, emojis) ?? shortcodeToEmoji(shortcode.replace(/\s+/g, '_'), emojis)
-          if (native?.emoji) return <Emoji key={index} emoji={native.emoji} classNames={{ img: 'size-4' }} />
+          if (native?.emoji)
+            return <Emoji key={index} emoji={native.emoji} classNames={{ img: EMOJI_IMG_INLINE_CLASS }} />
           return node.data
         }
         return node.data
diff --git a/src/components/Emoji/index.tsx b/src/components/Emoji/index.tsx
index 150c1a0c..6da1aac0 100644
--- a/src/components/Emoji/index.tsx
+++ b/src/components/Emoji/index.tsx
@@ -3,6 +3,11 @@ import { TEmoji } from '@/types'
 import { Heart, ThumbsDown } from 'lucide-react'
 import { HTMLAttributes, useState } from 'react'
 
+/** ~4/3 of legacy `size-5` for custom images when no `classNames.img` override. */
+export const EMOJI_IMG_DEFAULT_CLASS = 'size-[calc(1.25rem*4/3)]' as const
+/** ~4/3 of legacy `size-4` for dense inline contexts (markdown, likes row, etc.). */
+export const EMOJI_IMG_INLINE_CLASS = 'size-[calc(1rem*4/3)]' as const
+
 export default function Emoji({
   emoji,
   classNames,
@@ -20,11 +25,15 @@ export default function Emoji({
 
   if (typeof emoji === 'string') {
     if (emoji === '+') {
-      return <Heart className={cn('size-5 text-red-400 fill-red-400', classNames?.img)} />
+      return <Heart className={cn(EMOJI_IMG_DEFAULT_CLASS, 'text-red-400 fill-red-400', classNames?.img)} />
     }
     if (emoji === '-') {
       return (
-        <ThumbsDown className={cn('size-5 text-muted-foreground', classNames?.img)} strokeWidth={2} aria-hidden />
+        <ThumbsDown
+          className={cn(EMOJI_IMG_DEFAULT_CLASS, 'text-muted-foreground', classNames?.img)}
+          strokeWidth={2}
+          aria-hidden
+        />
       )
     }
     return <span className={cn('whitespace-nowrap', classNames?.text)}>{emoji}</span>
@@ -42,7 +51,8 @@ export default function Emoji({
       alt={emoji.shortcode}
       draggable={false}
       className={cn(
-        'inline-block size-5 rounded-sm',
+        'inline-block rounded-sm',
+        EMOJI_IMG_DEFAULT_CLASS,
         onImageClick ? 'cursor-zoom-in' : 'pointer-events-none',
         classNames?.img
       )}
diff --git a/src/components/Image/index.tsx b/src/components/Image/index.tsx
index 85fc3f34..4d9a1844 100644
--- a/src/components/Image/index.tsx
+++ b/src/components/Image/index.tsx
@@ -21,16 +21,25 @@ import { useTranslation } from 'react-i18next'
 /** Browsers often never fire `onError` for invalid URIs, ORB, or stalled fetches — this forces a visible error. */
 const IMAGE_LOAD_TIMEOUT_MS = 10_000
 
-/** Without reserved height, `absolute` skeleton + `opacity-0` img collapse to 0×0 — looks like “nothing”. */
+/**
+ * Without reserved height, `absolute` skeleton + `opacity-0` img collapse to 0×0 — looks like “nothing”.
+ * The tall `minHeight` fallback is only for that placeholder phase; keeping it after load (with no `dim`)
+ * leaves a box taller than the `<img>` when `height:100%` cannot resolve, which often reads as a white band
+ * under transparent GIFs or in dark UI.
+ */
 function wrapperReserveStyle(
   dim: { width: number; height: number } | undefined,
-  showError: boolean
+  showError: boolean,
+  useMinHeightPlaceholder: boolean
 ): CSSProperties | undefined {
   if (showError) return undefined
   if (dim && dim.width > 0 && dim.height > 0) {
     return { aspectRatio: `${dim.width} / ${dim.height}` }
   }
-  return { minHeight: 'min(30vh, 280px)' }
+  if (useMinHeightPlaceholder) {
+    return { minHeight: 'min(30vh, 280px)' }
+  }
+  return undefined
 }
 
 function formatFileSize(bytes: number): string {
@@ -50,6 +59,8 @@ export default function Image({
   holdUntilClick = false,
   fetchPriority,
   onClick,
+  showAltCaption = false,
+  caption,
   /** Native tooltip on hover (e.g. Markdown `![alt](url "title")`). When set, overrides alt-as-title on `<img>`. */
   tooltipTitle,
   ...props
@@ -62,6 +73,10 @@ export default function Image({
   alt?: string
   /** Shown as the `<img title>` tooltip when non-empty. */
   tooltipTitle?: string
+  /** When true, show {@link caption} or non-empty alt below the image (lightbox-style caption). */
+  showAltCaption?: boolean
+  /** Caption below the image; defaults to resolved alt when {@link showAltCaption} is true. */
+  caption?: string
   hideIfError?: boolean
   errorPlaceholder?: React.ReactNode
   /** Passed to the inner `<img>` (e.g. profile banner vs avatar load order). */
@@ -100,7 +115,17 @@ export default function Image({
   const imgTitle =
     tooltipTitle != null && String(tooltipTitle).trim() !== ''
       ? String(tooltipTitle).trim()
-      : finalAlt || undefined
+      : (() => {
+          const a = (finalAlt ?? '').trim()
+          // Markdown uses `alt="image"` when `![](url)` has no label — not a real caption/tooltip.
+          return a && a !== 'image' ? a : undefined
+        })()
+  const captionLine = (() => {
+    if (!showAltCaption) return ''
+    const c = (caption ?? finalAlt ?? '').trim()
+    if (c && c !== 'image') return c
+    return ''
+  })()
   const openLinkHref =
     (isSafeMediaUrl(url) && url.trim()) || (isSafeMediaUrl(imageUrl) && imageUrl.trim()) || ''
 
@@ -207,7 +232,11 @@ export default function Image({
     notifyLoaded()
   }
 
-  const reserveStyle = wrapperReserveStyle(dim, showErrorState)
+  const reserveStyle = wrapperReserveStyle(
+    dim,
+    showErrorState,
+    displaySkeleton && !showErrorState
+  )
   const mergedWrapperStyle: CSSProperties | undefined =
     reserveStyle || wrapperStyleProp
       ? { ...reserveStyle, ...wrapperStyleProp }
@@ -224,19 +253,20 @@ export default function Image({
     onClick?.(e)
   }
 
-  const titled = tooltipTitle != null && String(tooltipTitle).trim() !== ''
+  const hasHoverTip = Boolean(imgTitle)
 
   return (
-    <span
-      className={cn(
-        'relative overflow-hidden block w-full',
-        classNames.wrapper,
-        titled && 'cursor-help rounded-lg ring-1 ring-inset ring-dotted ring-muted-foreground/45'
-      )}
-      style={mergedWrapperStyle}
-      onClick={handleWrapperClick}
-      {...props}
-    >
+    <span className={cn('block w-full not-prose', classNames.wrapper)}>
+      <span
+        className={cn(
+          'relative overflow-hidden block w-full rounded-lg bg-background',
+          hasHoverTip && 'cursor-help ring-1 ring-inset ring-dotted ring-muted-foreground/45'
+        )}
+        style={mergedWrapperStyle}
+        title={imgTitle}
+        onClick={handleWrapperClick}
+        {...props}
+      >
       {displaySkeleton && !showErrorState && (
         <span className="absolute inset-0 z-10 block rounded-lg bg-muted/40">
           {effectiveBlurHash ? (
@@ -272,7 +302,6 @@ export default function Image({
           ref={imgRef}
           src={imageUrl}
           alt={finalAlt}
-          title={imgTitle}
           referrerPolicy="no-referrer"
           decoding={effectiveHoldUntilClick ? 'async' : 'sync'}
           // `lazy` often never starts the request inside nested feed scrollers; always-load should fetch eagerly.
@@ -319,6 +348,10 @@ export default function Image({
           ) : null}
         </span>
       )}
+      </span>
+      {captionLine ? (
+        <span className="mt-1 block px-1 text-center text-xs leading-snug text-muted-foreground">{captionLine}</span>
+      ) : null}
     </span>
   )
 }
diff --git a/src/components/Note/MarkdownArticle/MarkdownArticle.tsx b/src/components/Note/MarkdownArticle/MarkdownArticle.tsx
index a43a66e6..a0890c52 100644
--- a/src/components/Note/MarkdownArticle/MarkdownArticle.tsx
+++ b/src/components/Note/MarkdownArticle/MarkdownArticle.tsx
@@ -25,7 +25,7 @@ import { getHttpUrlFromITags, getImetaInfosFromEvent } from '@/lib/event'
 import { canonicalizeRssArticleUrl } from '@/lib/rss-article'
 import { cn } from '@/lib/utils'
 import { Event, kinds } from 'nostr-tools'
-import Emoji from '@/components/Emoji'
+import Emoji, { EMOJI_IMG_INLINE_CLASS } from '@/components/Emoji'
 import {
   ExtendedKind,
   SPOTIFY_OPEN_URL_REGEX,
@@ -3374,6 +3374,7 @@ function parseMarkdownContentMarked(
               image={{ ...baseImeta, url: src }}
               alt={label || 'image'}
               tooltipTitle={imageTip}
+              showAltCaption={Boolean(label.trim())}
               className="w-full rounded-lg cursor-zoom-in"
               classNames={{
                 wrapper: 'not-prose my-2 block max-w-[400px] mx-auto rounded-lg w-full',
@@ -4124,6 +4125,7 @@ function parseMarkdownContentMarked(
             image={imetaInfoForStandaloneImageUrl(cleaned)}
             alt={imageToken.text || 'image'}
             tooltipTitle={markdownTokenTitle(imageToken)}
+            showAltCaption={Boolean(String(imageToken.text ?? '').trim())}
             className="w-full rounded-lg cursor-zoom-in my-0"
             classNames={{ wrapper: 'my-2 block max-w-[400px] mx-auto' }}
             holdUntilClick={lazyMedia}
@@ -4913,7 +4915,7 @@ function parseInlineMarkdownLegacy(
           <Emoji
             key={`${keyPrefix}-emoji-${i}`}
             emoji={custom}
-            classNames={{ img: 'size-4 inline-block' }}
+            classNames={{ img: `${EMOJI_IMG_INLINE_CLASS} inline-block` }}
             onImageClick={
               typeof lbIdx === 'number' && emojiLightbox
                 ? () => emojiLightbox.openLightbox(lbIdx)
@@ -4924,7 +4926,9 @@ function parseInlineMarkdownLegacy(
       } else {
         const native = shortcodeToEmoji(shortcode, emojis) ?? shortcodeToEmoji(shortcode.replace(/\s+/g, '_'), emojis)
         if (native?.emoji) {
-          parts.push(<Emoji key={`${keyPrefix}-emoji-${i}`} emoji={native.emoji} classNames={{ img: 'size-4' }} />)
+          parts.push(
+            <Emoji key={`${keyPrefix}-emoji-${i}`} emoji={native.emoji} classNames={{ img: EMOJI_IMG_INLINE_CLASS }} />
+          )
         } else {
           parts.push(<span key={`${keyPrefix}-emoji-${i}`}>{`:${shortcode}:`}</span>)
         }
@@ -5244,7 +5248,15 @@ export default function MarkdownArticle({
       }
     }
     
+    const shortcodesInBody = new Set<string>()
+    const scRe = new RegExp(EMOJI_SHORT_CODE_REGEX.source, 'g')
+    let scMatch: RegExpExecArray | null
+    while ((scMatch = scRe.exec(event.content)) !== null) {
+      shortcodesInBody.add(scMatch[1].trim().toLowerCase())
+    }
+
     for (const em of emojiInfos) {
+      if (!shortcodesInBody.has(em.shortcode.trim().toLowerCase())) continue
       const raw = em.url?.trim()
       if (!raw) continue
       const cleaned = cleanUrl(raw)
@@ -5254,7 +5266,7 @@ export default function MarkdownArticle({
     }
 
     return images
-  }, [extractedMedia.images, metadata.image, emojiInfos])
+  }, [extractedMedia.images, metadata.image, emojiInfos, event.content])
 
   const lightboxSlides = useMemo(
     () => allImages.map((img) => lightboxSlideFromImeta(img)),
diff --git a/src/components/Note/ReactionEmojiDisplay.tsx b/src/components/Note/ReactionEmojiDisplay.tsx
index 176678cf..fdf899d5 100644
--- a/src/components/Note/ReactionEmojiDisplay.tsx
+++ b/src/components/Note/ReactionEmojiDisplay.tsx
@@ -68,10 +68,10 @@ export default function ReactionEmojiDisplay({
         classNames={{
           img:
             variant === 'thread'
-              ? 'size-3.5 max-h-[1em] w-auto rounded-sm opacity-90'
+              ? 'size-[calc(0.875rem*4/3)] max-h-[1em] w-auto rounded-sm opacity-90'
               : variant === 'compact'
-                ? 'size-4 max-h-[1em] w-auto rounded-sm'
-                : 'size-7 max-h-[1.5em] w-auto rounded-sm',
+                ? 'size-[calc(1rem*4/3)] max-h-[1em] w-auto rounded-sm'
+                : 'size-[calc(1.75rem*4/3)] max-h-[1.5em] w-auto rounded-sm',
           text:
             variant === 'thread'
               ? 'text-sm leading-none'
diff --git a/src/components/NoteOptions/EditOrCloneEventDialog.tsx b/src/components/NoteOptions/EditOrCloneEventDialog.tsx
index f3d65733..fbce4a97 100644
--- a/src/components/NoteOptions/EditOrCloneEventDialog.tsx
+++ b/src/components/NoteOptions/EditOrCloneEventDialog.tsx
@@ -378,6 +378,14 @@ export default function EditOrCloneEventDialog(props: EditOrCloneEventDialogProp
 
   const labKind = isCreate ? (parsedCreateKind ?? 0) : sourceEvent?.kind ?? 0
 
+  const labPreviewEmojiTags = useMemo(
+    () =>
+      !isCreate && sourceEvent?.tags?.length
+        ? sourceEvent.tags.filter(([n]) => n === 'emoji').map((row) => [...row])
+        : [],
+    [isCreate, sourceEvent]
+  )
+
   return (
     <>
     <Dialog open={open} onOpenChange={onOpenChange}>
@@ -601,6 +609,8 @@ export default function EditOrCloneEventDialog(props: EditOrCloneEventDialogProp
       markupMode={isAsciidocMarkupKind(labKind) ? 'asciidoc' : 'markdown'}
       i18nLanguage={i18n.language}
       contextEventId={!isCreate && sourceEvent ? sourceEvent.id : null}
+      previewAuthorPubkey={pubkey ?? null}
+      previewEmojiTags={labPreviewEmojiTags}
       draftPersistenceKey={
         advancedLabOpen && advancedLabDraftPersistenceKey ? advancedLabDraftPersistenceKey : null
       }
diff --git a/src/components/NoteStats/LikeButton.tsx b/src/components/NoteStats/LikeButton.tsx
index 0bc0452e..765d721a 100644
--- a/src/components/NoteStats/LikeButton.tsx
+++ b/src/components/NoteStats/LikeButton.tsx
@@ -32,7 +32,7 @@ import { Event } from 'nostr-tools'
 import { useMemo, useState } from 'react'
 import logger from '@/lib/logger'
 import { useTranslation } from 'react-i18next'
-import Emoji from '../Emoji'
+import Emoji, { EMOJI_IMG_INLINE_CLASS } from '../Emoji'
 import EmojiPicker, { EMOJI_PICKER_REACTIONS } from '../EmojiPicker'
 import {
   type RelayStatus,
@@ -234,7 +234,7 @@ export default function LikeButton({ event, hideCount = false }: { event: Event;
         <Skeleton className="size-4 shrink-0 rounded-full" aria-hidden />
       ) : myLastEmoji ? (
         <>
-          <Emoji emoji={inQuietMode ? '+' : myLastEmoji} classNames={{ img: 'size-4' }} />
+          <Emoji emoji={inQuietMode ? '+' : myLastEmoji} classNames={{ img: EMOJI_IMG_INLINE_CLASS }} />
           {!hideCount && statsLoaded && (
             <div className="text-sm tabular-nums">
               {(likeCount ?? 0) >= 100 ? '99+' : String(likeCount ?? 0)}
diff --git a/src/components/NoteStats/Likes.tsx b/src/components/NoteStats/Likes.tsx
index 9816d8dd..7e590385 100644
--- a/src/components/NoteStats/Likes.tsx
+++ b/src/components/NoteStats/Likes.tsx
@@ -12,7 +12,7 @@ import storage from '@/services/local-storage.service'
 import { TEmoji } from '@/types'
 import { Event } from 'nostr-tools'
 import { useMemo, useRef, useState } from 'react'
-import Emoji from '../Emoji'
+import Emoji, { EMOJI_IMG_INLINE_CLASS } from '../Emoji'
 import Username from '../Username'
 import logger from '@/lib/logger'
 
@@ -179,7 +179,7 @@ export default function Likes({ event }: { event: Event }) {
                           animation: isCompleted === key ? 'shake 0.5s ease-in-out infinite' : undefined
                         }}
                       >
-                        <Emoji emoji={emoji} classNames={{ img: 'size-4' }} />
+                        <Emoji emoji={emoji} classNames={{ img: EMOJI_IMG_INLINE_CLASS }} />
                       </div>
                     )}
                     <div className="text-sm">{pubkeys.size}</div>
diff --git a/src/components/PostEditor/PostContent.tsx b/src/components/PostEditor/PostContent.tsx
index a3bdffda..48709035 100644
--- a/src/components/PostEditor/PostContent.tsx
+++ b/src/components/PostEditor/PostContent.tsx
@@ -3595,6 +3595,7 @@ export default function PostContent({
         markupMode={isAsciidocMarkupKind(getDeterminedKind) ? 'asciidoc' : 'markdown'}
         i18nLanguage={i18n.language}
         contextEventId={parentEvent?.id ?? null}
+        previewAuthorPubkey={pubkey ?? null}
         draftPersistenceKey={advancedLabOpen ? advancedLabPersistenceKey : null}
         bodyApiRef={advancedLabBodyApiRef}
         formatToolbar={
diff --git a/src/i18n/locales/de.ts b/src/i18n/locales/de.ts
index 59a4bfea..8d5b72ed 100644
--- a/src/i18n/locales/de.ts
+++ b/src/i18n/locales/de.ts
@@ -959,6 +959,8 @@ export default {
     'Advanced lab cancel undo': 'Abbrechen und Änderungen verwerfen',
     'Advanced lab markup label markdown': 'Markdown',
     'Advanced lab markup label asciidoc': 'AsciiDoc',
+    'Advanced lab preview': 'Vorschau',
+    'Advanced lab preview empty': 'Noch nichts in der Vorschau.',
     'Advanced lab markup placeholder markdown': 'Notiztext (Markdown)',
     'Advanced lab markup placeholder asciidoc': 'Notiztext (AsciiDoc)',
     'Advanced lab tags JSON': 'Kind, Inhalt und Tags (JSON)',
diff --git a/src/i18n/locales/en.ts b/src/i18n/locales/en.ts
index b0c89c56..91f57c1a 100644
--- a/src/i18n/locales/en.ts
+++ b/src/i18n/locales/en.ts
@@ -960,6 +960,8 @@ export default {
     'Advanced lab cancel undo': 'Cancel and Undo Changes',
     'Advanced lab markup label markdown': 'Markdown',
     'Advanced lab markup label asciidoc': 'AsciiDoc',
+    'Advanced lab preview': 'Preview',
+    'Advanced lab preview empty': 'Nothing to preview yet.',
     'Advanced lab markup placeholder markdown': 'Note body (Markdown)',
     'Advanced lab markup placeholder asciidoc': 'Note body (AsciiDoc)',
     'Advanced lab tags JSON': 'Kind, content, and tags (JSON)',
diff --git a/src/lib/advanced-lab-markup-protect.test.ts b/src/lib/advanced-lab-markup-protect.test.ts
new file mode 100644
index 00000000..e84d68ed
--- /dev/null
+++ b/src/lib/advanced-lab-markup-protect.test.ts
@@ -0,0 +1,249 @@
+import { describe, expect, it, vi } from 'vitest'
+import {
+  getMarkupProtectRanges,
+  rangeIntersectsMerged,
+  translateAdvancedLabMarkup
+} from '@/lib/advanced-lab-markup-protect'
+
+vi.mock('@/lib/translate-client', () => ({
+  translatePlainText: vi.fn(async (text: string) => `<${text}>`)
+}))
+
+describe('getMarkupProtectRanges', () => {
+  it('freezes ATX heading marker and following whitespace', () => {
+    const merged = getMarkupProtectRanges('# Hello', 'markdown')
+    expect(merged.some(([a, b]) => a === 0 && b === 2)).toBe(true)
+  })
+
+  it('freezes inline math including delimiters', () => {
+    const t = 'a $\\sqrt{x}$ b'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const i0 = t.indexOf('$')
+    const i1 = t.indexOf('$', i0 + 1)
+    expect(i0).toBeGreaterThanOrEqual(0)
+    expect(i1).toBeGreaterThan(i0)
+    expect(rangeIntersectsMerged(i0, i1 - i0 + 1, merged)).toBe(true)
+  })
+
+  it('freezes display math', () => {
+    const t = 'pre $$a+b$$ post'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const start = t.indexOf('$$')
+    expect(rangeIntersectsMerged(start, 2, merged)).toBe(true)
+  })
+
+  it('respects CRLF when matching line-leading markup', () => {
+    const t = '# A\r\nplain'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(merged.some(([a, b]) => a === 0 && b === 2)).toBe(true)
+  })
+
+  it('freezes a fenced code block by line scanning', () => {
+    const t = '```js\nx\n```\n# H'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(merged.some(([a, b]) => a === 0 && b >= t.indexOf('```', 3) + 3)).toBe(true)
+    const hashLine = t.lastIndexOf('#')
+    expect(rangeIntersectsMerged(hashLine, 2, merged)).toBe(true)
+  })
+
+  it('markdown: freezes each pipe in a GFM-style table row', () => {
+    const t = '| Cell | Other |'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const pipes = [...t.matchAll(/\|/g)].map((m) => m.index!)
+    for (const idx of pipes) {
+      expect(rangeIntersectsMerged(idx, 1, merged)).toBe(true)
+    }
+  })
+
+  it('markdown: freezes alignment separator line as a whole', () => {
+    const t = '| --- | :---: |'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(merged.some(([a, b]) => a === 0 && b === t.length)).toBe(true)
+  })
+
+  it('markdown: freezes link brackets and URL part, not label', () => {
+    const t = '[Label](https://a.com)'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(rangeIntersectsMerged(0, 1, merged)).toBe(true)
+    expect(rangeIntersectsMerged(t.indexOf(']'), 1, merged)).toBe(true)
+    expect(rangeIntersectsMerged(t.indexOf('L'), 5, merged)).toBe(false)
+  })
+
+  it('markdown: link title in quotes is not frozen (only quotes and URL)', () => {
+    const t = '[L](https://a.com "Link title")'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const titleBodyStart = t.indexOf('Link title')
+    expect(rangeIntersectsMerged(titleBodyStart, 'Link title'.length, merged)).toBe(false)
+    expect(rangeIntersectsMerged(t.indexOf('"'), 1, merged)).toBe(true)
+  })
+
+  it('markdown: freezes footnote reference span', () => {
+    const t = 'See[^1]here'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(rangeIntersectsMerged(3, 4, merged)).toBe(true)
+  })
+
+  it('markdown: freezes NIP emoji shortcode span', () => {
+    const t = 'hi :chad_yes: bye'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const i = t.indexOf(':chad_yes:')
+    expect(rangeIntersectsMerged(i, ':chad_yes:'.length, merged)).toBe(true)
+  })
+
+  it('markdown: freezes inline code span', () => {
+    const t = 'a `code` b'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(rangeIntersectsMerged(t.indexOf('`'), 6, merged)).toBe(true)
+  })
+
+  it('asciidoc: freezes source block including fences', () => {
+    const t = '[source,js]\n----\nconst x = 1\n----\n'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && b === t.length)).toBe(true)
+  })
+
+  it('asciidoc: freezes stem macro span', () => {
+    const t = 'x stem:[\\alpha] y'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    const s = t.indexOf('stem:')
+    expect(rangeIntersectsMerged(s, 'stem:[\\alpha]'.length, merged)).toBe(true)
+  })
+
+  it('freezes wiki double-bracket spans (bookstr, citation, wikis)', () => {
+    const t = '[[wikis|Nostr]] [[book::genesis]] [[citation::inline::x]]'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(merged.some(([a, b]) => t.slice(a, b) === '[[wikis|Nostr]]')).toBe(true)
+    expect(merged.some(([a, b]) => t.slice(a, b) === '[[book::genesis]]')).toBe(true)
+    expect(merged.some(([a, b]) => t.slice(a, b).startsWith('[[citation::'))).toBe(true)
+  })
+
+  it('freezes nostr: and bare npub1', () => {
+    const npub = 'npub1' + 'q'.repeat(58)
+    const t = `x nostr:${npub} y ${npub} z`
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    const atNostr = t.indexOf('nostr:')
+    expect(rangeIntersectsMerged(atNostr, `nostr:${npub}`.length, merged)).toBe(true)
+    expect(rangeIntersectsMerged(t.lastIndexOf(npub), npub.length, merged)).toBe(true)
+  })
+
+  it('freezes BOOKSTR_MARKER passthrough and WIKILINK marker', () => {
+    const book = 'BOOKSTR_MARKER:foo:BOOKSTR_END'
+    const wiki = 'WIKILINK:my-page[My Page]'
+    const merged = getMarkupProtectRanges(`${book} ${wiki}`, 'markdown')
+    expect(merged.some(([a, b]) => a === 0 && b === book.length)).toBe(true)
+    expect(merged.some(([a, b]) => b - a === wiki.length)).toBe(true)
+  })
+
+  it('freezes link: and menu: bracket macros in markdown', () => {
+    const t = 'link:https://x.com[Go] menu:File[Quit]'
+    const merged = getMarkupProtectRanges(t, 'markdown')
+    expect(merged.some(([a, b]) => t.slice(a, b) === 'link:https://x.com[Go]')).toBe(true)
+    expect(merged.some(([a, b]) => t.slice(a, b) === 'menu:File[Quit]')).toBe(true)
+  })
+
+  it('asciidoc: freezes section title prefix', () => {
+    const merged = getMarkupProtectRanges('= Title', 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && b === 2)).toBe(true)
+  })
+
+  it('asciidoc: freezes unordered and ordered list markers', () => {
+    const star = getMarkupProtectRanges('* one', 'asciidoc')
+    expect(star.some(([a, b]) => a === 0 && b === 2)).toBe(true)
+    const dot = getMarkupProtectRanges('.. two', 'asciidoc')
+    expect(dot.some(([a, b]) => a === 0 && b === 3)).toBe(true)
+  })
+
+  it('asciidoc: freezes labeled list marker', () => {
+    const t = 'CPU:: The brain'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && t.slice(a, b) === 'CPU:: ')).toBe(true)
+  })
+
+  it('asciidoc: freezes attribute name and following spaces', () => {
+    const t = ':toc: Table of contents'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && t.slice(a, b) === ':toc: ')).toBe(true)
+  })
+
+  it('asciidoc: freezes whole-line include macro', () => {
+    const t = 'include::chapter.adoc[]'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && b === t.length)).toBe(true)
+  })
+
+  it('asciidoc: delimiter line is fully frozen', () => {
+    const t = '----'
+    const merged = getMarkupProtectRanges(t, 'asciidoc')
+    expect(merged.some(([a, b]) => a === 0 && b === t.length)).toBe(true)
+  })
+})
+
+describe('translateAdvancedLabMarkup', () => {
+  it('translates heading text but not the # prefix', async () => {
+    const out = await translateAdvancedLabMarkup('# Title', 'de', 'en', 'markdown')
+    expect(out).toBe('# <Title>')
+  })
+
+  it('does not send math delimiters or body to translate', async () => {
+    const t = 'x $\\sqrt{y}$ z'
+    const out = await translateAdvancedLabMarkup(t, 'de', 'en', 'markdown')
+    expect(out).toContain('$\\sqrt{y}$')
+    expect(out).toBe('<x >$\\sqrt{y}$< z>')
+  })
+
+  it('asciidoc: translates heading text after equals marker', async () => {
+    const out = await translateAdvancedLabMarkup('= Title', 'de', 'en', 'asciidoc')
+    expect(out).toBe('= <Title>')
+  })
+
+  it('markdown: translates table cell text but not pipes', async () => {
+    const out = await translateAdvancedLabMarkup('| Cell |', 'ru', 'en', 'markdown')
+    expect(out).toBe('|< Cell >|')
+  })
+
+  it('markdown: leaves separator row unchanged', async () => {
+    const t = '| --- | --- |\n| a | b |'
+    const out = await translateAdvancedLabMarkup(t, 'ru', 'en', 'markdown')
+    expect(out).toContain('| --- | --- |')
+    expect(out).toMatch(/\|\s*< a >\s*\|/)
+  })
+
+  it('markdown: translates link label only', async () => {
+    const out = await translateAdvancedLabMarkup('[Hi](https://x.com)', 'de', 'en', 'markdown')
+    expect(out).toBe('[<Hi>](https://x.com)')
+  })
+
+  it('markdown: translates optional link title in quotes', async () => {
+    const out = await translateAdvancedLabMarkup(
+      '[Hi](https://x.com "Link title")',
+      'de',
+      'en',
+      'markdown'
+    )
+    expect(out).toBe('[<Hi>](https://x.com "<Link title>")')
+  })
+
+  it('markdown: does not translate :shortcode: spans', async () => {
+    const out = await translateAdvancedLabMarkup('Hello :chad_yes: world', 'de', 'en', 'markdown')
+    expect(out).toBe('<Hello >:chad_yes:< world>')
+  })
+
+  it('preserves newlines: translate API is never called with embedded line breaks', async () => {
+    const { translatePlainText } = await import('@/lib/translate-client')
+    const spy = vi.mocked(translatePlainText)
+    spy.mockClear()
+    spy.mockImplementation(async (s: string) => `<${s}>`)
+    await translateAdvancedLabMarkup('Line1\nLine2', 'de', 'en', 'markdown')
+    for (const call of spy.mock.calls) {
+      expect(String(call[0])).not.toMatch(/\r|\n/)
+    }
+    expect(spy.mock.calls.map((c) => c[0])).toEqual(['Line1', 'Line2'])
+  })
+
+  it('preserves blank lines between translated lines', async () => {
+    const { translatePlainText } = await import('@/lib/translate-client')
+    vi.mocked(translatePlainText).mockImplementation(async (s: string) => (s === 'A' ? 'Aa' : 'Bb'))
+    const out = await translateAdvancedLabMarkup('A\n\nB', 'de', 'en', 'markdown')
+    expect(out).toBe('Aa\n\nBb')
+  })
+})
diff --git a/src/lib/advanced-lab-markup-protect.ts b/src/lib/advanced-lab-markup-protect.ts
new file mode 100644
index 00000000..e648d6ad
--- /dev/null
+++ b/src/lib/advanced-lab-markup-protect.ts
@@ -0,0 +1,995 @@
+/**
+ * Ranges in the lab editor source that must not be grammar-checked or machine-translated.
+ * Covers Advanced Event Lab toolbar constructs: headings, lists, quotes, tables, code fences,
+ * math ($ / $$), Markdown links/images (structure only), task items, footnotes, inline code,
+ * emphasis/strike delimiters, and AsciiDoc blocks, macros, stem, passthrough, xref.
+ * Also: wiki `[[…]]` (incl. `book::`, `citation::`), `wikilink:`, `BOOKSTR_MARKER:…:BOOKSTR_END`,
+ * `nostr:…` / bare NIP-19 bech32 (`npub1`…, `nprofile1`…, etc.), and `link:url[text]` macros.
+ * NIP-style custom/native emoji shortcodes `:shortcode:` (see {@link EMOJI_SHORT_CODE_REGEX}).
+ */
+
+import { EMOJI_SHORT_CODE_REGEX } from '@/lib/content-patterns'
+import { translatePlainText } from '@/lib/translate-client'
+
+export type AdvancedLabMarkupMode = 'markdown' | 'asciidoc'
+
+function mergeSortedRanges(ranges: [number, number][]): [number, number][] {
+  if (ranges.length === 0) return []
+  const s = [...ranges].sort((a, b) => a[0] - b[0] || a[1] - b[1])
+  const out: [number, number][] = []
+  let [cs, ce] = s[0]!
+  for (let i = 1; i < s.length; i++) {
+    const [a, b] = s[i]!
+    if (a <= ce) ce = Math.max(ce, b)
+    else {
+      out.push([cs, ce])
+      cs = a
+      ce = b
+    }
+  }
+  out.push([cs, ce])
+  return out
+}
+
+function posInMerged(pos: number, merged: [number, number][]): boolean {
+  return merged.some(([a, b]) => pos >= a && pos < b)
+}
+
+/** Walk logical lines; `lineStart` is index of first char, `raw` has no line ending. */
+function forEachLine(
+  text: string,
+  cb: (raw: string, lineStart: number, lineIndex: number) => void
+): void {
+  const lines = text.split(/\r?\n/)
+  let lineStart = 0
+  for (let li = 0; li < lines.length; li++) {
+    cb(lines[li]!, lineStart, li)
+    lineStart += lines[li]!.length
+    if (li < lines.length - 1) {
+      if (text[lineStart] === '\r' && text[lineStart + 1] === '\n') lineStart += 2
+      else lineStart += 1
+    }
+  }
+}
+
+/** Find closing `$` for inline math starting after opening `$` at index `open + 1`. */
+function findClosingInlineDollar(text: string, open: number): number {
+  let j = open + 1
+  while (j < text.length) {
+    const c = text[j]
+    if (c === '\\' && j + 1 < text.length) {
+      j += 2
+      continue
+    }
+    if (c === '$') return j
+    j++
+  }
+  return -1
+}
+
+function collectLatexRanges(text: string): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length) {
+    if (text.startsWith('$$', i)) {
+      const close = text.indexOf('$$', i + 2)
+      if (close === -1) break
+      ranges.push([i, close + 2])
+      i = close + 2
+      continue
+    }
+    if (text[i] === '$') {
+      const close = findClosingInlineDollar(text, i)
+      if (close < 0) {
+        i++
+        continue
+      }
+      ranges.push([i, close + 1])
+      i = close + 1
+      continue
+    }
+    i++
+  }
+  return ranges
+}
+
+function collectFencedCodeRanges(text: string): [number, number][] {
+  const ranges: [number, number][] = []
+  const n = text.length
+  let i = 0
+  while (i < n) {
+    if (!text.startsWith('```', i)) {
+      i++
+      continue
+    }
+    if (i > 0 && text[i - 1] !== '\n' && text[i - 1] !== '\r') {
+      i++
+      continue
+    }
+    const firstNl = text.indexOf('\n', i)
+    const bodyStart = firstNl === -1 ? n : firstNl + 1
+    let p = bodyStart
+    let blockEnd = -1
+    while (p <= n) {
+      const nl = text.indexOf('\n', p)
+      const lineEnd = nl === -1 ? n : nl
+      const line = text.slice(p, lineEnd)
+      if (/^[\t ]{0,3}```(?:\s|$)/.test(line)) {
+        blockEnd = nl === -1 ? n : nl + 1
+        break
+      }
+      if (nl === -1) break
+      p = nl + 1
+    }
+    if (blockEnd < 0) {
+      i = bodyStart
+      continue
+    }
+    ranges.push([i, blockEnd])
+    i = blockEnd
+  }
+  return ranges
+}
+
+/** GFM-style column alignment row: pipes, colons, dashes, spaces only, and at least one dash. */
+function looksLikePipeTableSeparatorRow(line: string): boolean {
+  const t = line.trim()
+  if (!t.includes('|')) return false
+  if (!/^[\s|\-:]+$/.test(t)) return false
+  if (!/-/.test(t)) return false
+  return true
+}
+
+function collectPipeTableRanges(text: string, mergedBase: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const lines = text.split(/\r?\n/)
+  const rowFlags = lines.map((rawLine) => {
+    let pipeCount = 0
+    for (let j = 0; j < rawLine.length; j++) {
+      if (rawLine[j] === '|') pipeCount++
+    }
+    const isSep = looksLikePipeTableSeparatorRow(rawLine)
+    return isSep || pipeCount >= 2
+  })
+
+  let lineStart = 0
+  let prevWasTableRow = false
+  for (let li = 0; li < lines.length; li++) {
+    const rawLine = lines[li]!
+    const isTableRow = rowFlags[li]!
+
+    if (li > 0 && prevWasTableRow && isTableRow) {
+      let gapStart = lineStart - 1
+      if (gapStart >= 1 && text[gapStart] === '\n' && text[gapStart - 1] === '\r') gapStart -= 1
+      if (gapStart < lineStart) ranges.push([gapStart, lineStart])
+    }
+
+    if (isTableRow) {
+      const isSep = looksLikePipeTableSeparatorRow(rawLine)
+      if (isSep) {
+        const a = lineStart
+        const b = lineStart + rawLine.length
+        if (a < b && !posInMerged(a, mergedBase)) ranges.push([a, b])
+      } else {
+        for (let j = 0; j < rawLine.length; j++) {
+          if (rawLine[j] !== '|') continue
+          const g = lineStart + j
+          if (!posInMerged(g, mergedBase)) ranges.push([g, g + 1])
+        }
+      }
+    }
+
+    prevWasTableRow = isTableRow
+    lineStart += rawLine.length
+    if (li < lines.length - 1) {
+      if (text[lineStart] === '\r' && text[lineStart + 1] === '\n') lineStart += 2
+      else lineStart += 1
+    }
+  }
+  return ranges
+}
+
+function findClosingParenMdUrl(text: string, openParen: number): number {
+  let i = openParen
+  let depth = 0
+  let inStr: '"' | "'" | null = null
+  while (i < text.length) {
+    const c = text[i]
+    if (inStr) {
+      if (c === '\\' && i + 1 < text.length) {
+        i += 2
+        continue
+      }
+      if (c === inStr) inStr = null
+      i++
+      continue
+    }
+    if (c === '"' || c === "'") {
+      inStr = c
+      i++
+      continue
+    }
+    if (c === '(') depth++
+    else if (c === ')') {
+      depth--
+      if (depth === 0) return i + 1
+    }
+    i++
+  }
+  return -1
+}
+
+/** Walk label inside `[...]` starting at `labelStart` (first char inside brackets). */
+function findLabelEndBracket(text: string, labelStart: number): number {
+  let j = labelStart
+  while (j < text.length) {
+    const c = text[j]
+    if (c === '\\' && j + 1 < text.length) {
+      j += 2
+      continue
+    }
+    if (c === ']') return j
+    j++
+  }
+  return -1
+}
+
+/**
+ * Inside `[...](` … `)`, find optional CommonMark title after the destination.
+ * Returns indices relative to `inner` (slice between `(` and closing `)`).
+ */
+function parseMdInlineLinkDestForTitle(inner: string): {
+  /** Freeze [0, titleQuoteIdx) — destination + whitespace before title. */
+  titleQuoteIdx: number
+  /** Freeze [closeQuoteIdx, closeQuoteIdx + 1) — closing quote. */
+  closeQuoteIdx: number
+} | null {
+  if (!inner) return null
+  let hrefEnd = 0
+  if (inner[0] === '<') {
+    let j = 1
+    while (j < inner.length) {
+      if (inner[j] === '\\' && j + 1 < inner.length) {
+        j += 2
+        continue
+      }
+      if (inner[j] === '>') {
+        hrefEnd = j + 1
+        break
+      }
+      j++
+    }
+    if (hrefEnd === 0) hrefEnd = inner.length
+  } else {
+    const m = inner.match(/^\S+/)
+    if (!m) return null
+    hrefEnd = m[0].length
+  }
+  let p = hrefEnd
+  while (p < inner.length && /\s/.test(inner[p]!)) p++
+  if (p >= inner.length) return null
+  const q = inner[p]
+  if (q !== '"' && q !== "'") return null
+  const bodyStart = p + 1
+  let j = bodyStart
+  while (j < inner.length) {
+    if (inner[j] === '\\' && j + 1 < inner.length) {
+      j += 2
+      continue
+    }
+    if (inner[j] === q) return { titleQuoteIdx: p, closeQuoteIdx: j }
+    j++
+  }
+  return null
+}
+
+/** Push frozen ranges for `](` … `)`; link title body (between quotes) stays translatable. */
+function pushMarkdownLinkParenStructureRanges(
+  ranges: [number, number][],
+  text: string,
+  lbEnd: number,
+  parenEnd: number
+): void {
+  const innerStart = lbEnd + 2
+  const closeParenIdx = parenEnd - 1
+  ranges.push([lbEnd, innerStart])
+  const inner = text.slice(innerStart, closeParenIdx)
+  const titled = parseMdInlineLinkDestForTitle(inner)
+  if (!titled) {
+    ranges.push([innerStart, parenEnd])
+    return
+  }
+  const { titleQuoteIdx, closeQuoteIdx } = titled
+  ranges.push([innerStart, innerStart + titleQuoteIdx])
+  ranges.push([innerStart + titleQuoteIdx, innerStart + titleQuoteIdx + 1])
+  ranges.push([innerStart + closeQuoteIdx, innerStart + closeQuoteIdx + 1])
+  ranges.push([closeParenIdx, parenEnd])
+}
+
+/** Markdown / CommonMark `link` and `image` — freeze brackets/URL/title quotes; label + title body translate. */
+function collectMarkdownLinkImageStructureRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length - 1) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    const isImg = text.startsWith('![', i)
+    const isLink = text[i] === '[' && text[i + 1] !== '^' && text[i + 1] !== '['
+    if (!isImg && !isLink) {
+      i++
+      continue
+    }
+    const labelStart = isImg ? i + 2 : i + 1
+    const lbEnd = findLabelEndBracket(text, labelStart)
+    if (lbEnd < 0 || lbEnd + 1 >= text.length || text[lbEnd + 1] !== '(') {
+      i++
+      continue
+    }
+    const parenEnd = findClosingParenMdUrl(text, lbEnd + 1)
+    if (parenEnd < 0) {
+      i++
+      continue
+    }
+    if (isImg) ranges.push([i, i + 2])
+    else ranges.push([i, i + 1])
+    pushMarkdownLinkParenStructureRanges(ranges, text, lbEnd, parenEnd)
+    i = parenEnd
+  }
+  return ranges
+}
+
+/** `[^id]` reference (not definition line — handled by line prefix). */
+function collectMarkdownFootnoteRefRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length - 2) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (text[i] !== '[' || text[i + 1] !== '^') {
+      i++
+      continue
+    }
+    const j = findLabelEndBracket(text, i + 2)
+    if (j < 0 || j === i + 2) {
+      i++
+      continue
+    }
+    ranges.push([i, j + 1])
+    i = j + 1
+  }
+  return ranges
+}
+
+/** Fenced code spans with run of backticks (CommonMark). */
+function collectInlineCodeRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (text[i] !== '`') {
+      i++
+      continue
+    }
+    let n = 0
+    let p = i
+    while (p < text.length && text[p] === '`') {
+      n++
+      p++
+    }
+    let q = p
+    let found = -1
+    while (q < text.length) {
+      if (text[q] === '`') {
+        let m = 0
+        let r = q
+        while (r < text.length && text[r] === '`') {
+          m++
+          r++
+        }
+        if (m >= n) {
+          found = r
+          break
+        }
+        q = r
+        continue
+      }
+      q++
+    }
+    if (found < 0) break
+    ranges.push([i, found])
+    i = found
+  }
+  return ranges
+}
+
+/** Freeze only `**` / `__` / `~~` delimiter pairs so inner text still translates (toolbar inline). */
+function collectMarkdownDelimiterPairEdges(
+  text: string,
+  merged: [number, number][],
+  token: string
+): [number, number][] {
+  const ranges: [number, number][] = []
+  const tl = token.length
+  if (tl < 2) return ranges
+  let i = 0
+  while (i <= text.length - tl * 2) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (!text.startsWith(token, i)) {
+      i++
+      continue
+    }
+    let j = i + tl
+    while (j <= text.length - tl) {
+      if (posInMerged(j, merged)) {
+        j++
+        continue
+      }
+      if (text.startsWith(token, j)) {
+        ranges.push([i, i + tl], [j, j + tl])
+        i = j + tl
+        break
+      }
+      j++
+    }
+    if (j > text.length - tl) i++
+  }
+  return ranges
+}
+
+function matchAsciiDocLinePrefix(rawLine: string): RegExpMatchArray | null {
+  const patterns: RegExp[] = [
+    /^[\t ]{0,3}\/\/[^\n]*$/,
+    /^[\t ]{0,3}(?:-{4,}|\.{4,}|={4,}|\*{4,}|_{4,}|\+{4,}|\/{4,})\s*$/,
+    /^[\t ]{0,3}\|={3,}\s*$/,
+    /^[\t ]{0,3}(?:---|\*\*\*|___|''')\s*$/,
+    /^[\t ]{0,3}--\s*$/,
+    /^[\t ]{0,3}\+\s*$/,
+    /^[\t ]{0,3}=+\s+/,
+    /^[\t ]{0,3}(?:ifdef|ifndef|ifeval|endif)::[^\n]*$/,
+    /^[\t ]{0,3}(?:include|image|video|audio|xref|link|mailto|pass|kbd|btn|menu|anchor|set|footnote)::[^\n]*$/,
+    /^[\t ]{0,3}\[\[[^\]]+\]\]\s*/,
+    /^[\t ]{0,3}(\[[^\]\n]+\]\s*)$/,
+    /^[\t ]{0,3}(:[!]?[A-Za-z0-9_][\w-]*:)\s*/,
+    /^[\t ]{0,3}(?!https?:\/\/)(.+?::\s+)/,
+    /^[\t ]{0,3}\*{1,9}\s+/,
+    /^[\t ]{0,3}-\s+/,
+    /^[\t ]{0,3}\.{1,9}\s+/
+  ]
+  for (const re of patterns) {
+    const m = rawLine.match(re)
+    if (m) return m
+  }
+  return null
+}
+
+function collectLinePrefixRanges(
+  text: string,
+  mode: AdvancedLabMarkupMode,
+  mergedBase: [number, number][]
+): [number, number][] {
+  const ranges: [number, number][] = []
+  forEachLine(text, (rawLine, lineStart) => {
+    if (posInMerged(lineStart, mergedBase)) return
+    let m: RegExpMatchArray | null = null
+    if (mode === 'markdown') {
+      m =
+        rawLine.match(/^[\t ]{0,3}(#{1,6}\s+)/) ||
+        rawLine.match(/^[\t ]{0,3}(?:[-*+]\s+\[[ xX]\]\s+)/) ||
+        rawLine.match(/^[\t ]{0,3}(?:[-*+]\s+)/) ||
+        rawLine.match(/^[\t ]{0,3}(?:\d{1,9}\.\s+)/) ||
+        rawLine.match(/^[\t ]{0,3}(>\s?)/) ||
+        rawLine.match(/^[\t ]{0,3}(\[\^[^\]\n]+\]:)\s*/) ||
+        rawLine.match(/^[\t ]{0,3}(?:[-*]{3,}|_{3,})\s*$/) ||
+        rawLine.match(/^[\t ]{0,3}=+\s*$/) ||
+        rawLine.match(/^[\t ]{0,3}(?:`{3,}\s*)\S.*$/)
+    } else {
+      m = matchAsciiDocLinePrefix(rawLine)
+    }
+    if (m && m[0].length > 0) ranges.push([lineStart, lineStart + m[0].length])
+  })
+  return ranges
+}
+
+const ADOC_FENCE_LINE = /^[\t ]{0,3}(-{4,}|={4,}|\*{4,}|_{4,}|\.{4,}|\+{4,}|--)\s*$/
+
+function lineMatchFence(raw: string): string | null {
+  const t = raw.replace(/\r$/, '')
+  const m = t.match(ADOC_FENCE_LINE)
+  return m ? m[1]! : null
+}
+
+/** `[source,...]` or `[NOTE]` / `[TIP]` / … / `[stem]` / `[listing]` / `[example]` (toolbar blocks). */
+function isAdocBlockMetaLine(raw: string): boolean {
+  const t = raw.trim()
+  if (!/^\[[^\]]+\]$/.test(t)) return false
+  return /^\[\s*(source|NOTE|TIP|WARNING|IMPORTANT|CAUTION|stem|listing|example|discrete)/i.test(t)
+}
+
+function collectAsciiDocStructuredBlocks(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const lines = text.split(/\r?\n/)
+  let offset = 0
+  const lineStarts: number[] = []
+  for (let li = 0; li < lines.length; li++) {
+    lineStarts.push(offset)
+    offset += lines[li]!.length
+    if (li < lines.length - 1) {
+      if (text[offset] === '\r' && text[offset + 1] === '\n') offset += 2
+      else offset += 1
+    }
+  }
+
+  let li = 0
+  while (li < lines.length) {
+    const raw = lines[li]!
+    const ls = lineStarts[li]!
+    if (!posInMerged(ls, merged)) {
+      const meta = isAdocBlockMetaLine(raw)
+      let openFenceLine = li
+      let fenceToken: string | null = null
+      if (meta) {
+        let j = li + 1
+        while (j < lines.length && /^\s*$/.test(lines[j]!)) j++
+        if (j < lines.length) {
+          const f = lineMatchFence(lines[j]!)
+          if (f && (f === '----' || f === '====' || f === '++++')) {
+            openFenceLine = j
+            fenceToken = f
+          }
+        }
+      } else {
+        const f = lineMatchFence(raw)
+        if (
+          f &&
+          (f === '----' ||
+            f === '====' ||
+            f === '++++' ||
+            f === '****' ||
+            f === '____' ||
+            f === '....' ||
+            f === '--')
+        ) {
+          openFenceLine = li
+          fenceToken = f
+        }
+      }
+
+      if (fenceToken) {
+        let k = openFenceLine + 1
+        while (k < lines.length) {
+          if (lineMatchFence(lines[k]!) === fenceToken) {
+            const endLineIdx = k
+            let endOff = lineStarts[endLineIdx]! + lines[endLineIdx]!.length
+            if (endLineIdx < lines.length - 1) {
+              if (text[endOff] === '\r' && text[endOff + 1] === '\n') endOff += 2
+              else endOff += 1
+            }
+            const startOff = meta ? ls : lineStarts[openFenceLine]!
+            ranges.push([startOff, endOff])
+            li = endLineIdx
+            break
+          }
+          k++
+        }
+      }
+    }
+    li++
+  }
+  return ranges
+}
+
+function bracketDepthClose(text: string, from: number): number {
+  let d = 0
+  for (let p = from; p < text.length; p++) {
+    const c = text[p]
+    if (c === '\\' && p + 1 < text.length) {
+      p++
+      continue
+    }
+    if (c === '[') d++
+    else if (c === ']') {
+      d--
+      if (d === 0) return p + 1
+    }
+  }
+  return -1
+}
+
+function isAsciiDocMacroBoundary(text: string, i: number): boolean {
+  if (i === 0) return true
+  const prev = text[i - 1]!
+  return !/[a-zA-Z0-9_]/.test(prev)
+}
+
+/** AsciiDoc `stem:[…]`, `latexmath:[…]`, `footnote:[…]`, `kbd:[]`, `btn:[]`, `image::…[]`, `video::…`, `audio::…` (`link:` / `menu:` handled in {@link collectLinkMenuColonMacros}). */
+function collectAsciiDocInlineMacroRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const needles = [
+    'stem:[',
+    'latexmath:[',
+    'footnote:[',
+    'kbd:[',
+    'btn:[',
+    'image::',
+    'video::',
+    'audio::'
+  ] as const
+
+  let i = 0
+  while (i < text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    let hit: (typeof needles)[number] | null = null
+    for (const n of needles) {
+      if (text.startsWith(n, i) && isAsciiDocMacroBoundary(text, i)) {
+        hit = n
+        break
+      }
+    }
+    if (!hit) {
+      i++
+      continue
+    }
+    if (hit === 'image::' || hit === 'video::' || hit === 'audio::') {
+      const ob = text.indexOf('[', i + hit.length)
+      if (ob < 0) {
+        const nl = text.indexOf('\n', i)
+        ranges.push([i, nl === -1 ? text.length : nl + 1])
+        i++
+        continue
+      }
+      const end = bracketDepthClose(text, ob)
+      if (end < 0) {
+        i++
+        continue
+      }
+      ranges.push([i, end])
+      i = end
+      continue
+    }
+    const openBracket = i + hit.length - 1
+    if (text[openBracket] !== '[') {
+      i++
+      continue
+    }
+    const end = bracketDepthClose(text, openBracket)
+    if (end < 0) {
+      i++
+      continue
+    }
+    ranges.push([i, end])
+    i = end
+  }
+  return ranges
+}
+
+/** `+++passthrough+++` (toolbar). */
+function collectAsciiDocTriplePlusPassthrough(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i + 3 <= text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (!text.startsWith('+++', i)) {
+      i++
+      continue
+    }
+    const close = text.indexOf('+++', i + 3)
+    if (close < 0) break
+    ranges.push([i, close + 3])
+    i = close + 3
+  }
+  return ranges
+}
+
+/** `[[page]]`, `[[page|label]]`, `[[book::…]]`, `[[citation::…]]`, AsciiDoc `[[id]]`. */
+function collectWikiDoubleBracketRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i + 3 <= text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (!text.startsWith('[[', i)) {
+      i++
+      continue
+    }
+    const close = text.indexOf(']]', i + 2)
+    if (close < 0) break
+    ranges.push([i, close + 2])
+    i = close + 2
+  }
+  return ranges
+}
+
+/** Passthrough markers from article preprocessing (AsciiDoc / Markdown pipelines). */
+function collectBookstrMarkerPassthrough(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const head = 'BOOKSTR_MARKER:'
+  const tail = ':BOOKSTR_END'
+  let i = 0
+  while (i < text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    const s = text.indexOf(head, i)
+    if (s < 0) break
+    const e = text.indexOf(tail, s + head.length)
+    if (e < 0) {
+      i = s + 1
+      continue
+    }
+    if (!posInMerged(s, merged)) ranges.push([s, e + tail.length])
+    i = e + tail.length
+  }
+  return ranges
+}
+
+/** `wikilink:dtag[label]` (post-processed wiki / bookstr). */
+function collectWikilinkMarkerRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const re = /\bWIKILINK:([^\s[\n]+)(?:\[[^\]]*\])?/g
+  let m: RegExpExecArray | null
+  while ((m = re.exec(text))) {
+    const s = m.index
+    if (!posInMerged(s, merged)) ranges.push([s, s + m[0].length])
+  }
+  return ranges
+}
+
+/** AsciiDoc / Markdown `link:url[text]` and `menu:…[…]` (toolbar + jumble). */
+function collectLinkMenuColonMacros(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const prefixes = ['link:', 'menu:'] as const
+  let i = 0
+  while (i < text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    let hit: (typeof prefixes)[number] | null = null
+    for (const p of prefixes) {
+      if (text.startsWith(p, i) && isAsciiDocMacroBoundary(text, i)) {
+        hit = p
+        break
+      }
+    }
+    if (!hit) {
+      i++
+      continue
+    }
+    const ob = text.indexOf('[', i + hit.length)
+    if (ob < 0) {
+      i++
+      continue
+    }
+    const end = bracketDepthClose(text, ob)
+    if (end < 0) {
+      i++
+      continue
+    }
+    ranges.push([i, end])
+    i = end
+  }
+  return ranges
+}
+
+const B32 = '[ac-hj-np-z02-9]'
+const RE_NOSTR_PREFIX = new RegExp(
+  `^nostr:(npub1${B32}{58}|nprofile1${B32}{20,}|note1${B32}{20,}|nevent1${B32}{20,}|naddr1${B32}{20,}|nrelay1${B32}{20,})(?!${B32})`,
+  'i'
+)
+const RE_NPUB_BARE = new RegExp(`^npub1${B32}{58}(?!${B32})`, 'i')
+const RE_BARE_OTHER = new RegExp(
+  `^((?:nprofile|note|nevent|naddr|nrelay)1${B32}{20,})(?!${B32})`,
+  'i'
+)
+
+/** `nostr:npub1…` / `nostr:nevent1…` and bare NIP-19 bech32 entities. */
+function collectNostrAndBech32Ranges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (i > 0 && /[a-zA-Z0-9_]/.test(text[i - 1]!)) {
+      i++
+      continue
+    }
+    const slice = text.slice(i)
+    const prefixed = slice.match(RE_NOSTR_PREFIX)
+    if (prefixed) {
+      ranges.push([i, i + prefixed[0].length])
+      i += prefixed[0].length
+      continue
+    }
+    const npub = slice.match(RE_NPUB_BARE)
+    if (npub) {
+      ranges.push([i, i + npub[0].length])
+      i += npub[0].length
+      continue
+    }
+    const other = slice.match(RE_BARE_OTHER)
+    if (other) {
+      ranges.push([i, i + other[0].length])
+      i += other[0].length
+      continue
+    }
+    i++
+  }
+  return ranges
+}
+
+/** AsciiDoc `<<id,label>>` / `<<id>>`. */
+function collectAsciiDocXrefRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  let i = 0
+  while (i < text.length - 3) {
+    if (posInMerged(i, merged)) {
+      i++
+      continue
+    }
+    if (!text.startsWith('<<', i)) {
+      i++
+      continue
+    }
+    const close = text.indexOf('>>', i + 2)
+    if (close < 0) break
+    ranges.push([i, close + 2])
+    i = close + 2
+  }
+  return ranges
+}
+
+/** `:shortcode:` spans (custom / native emoji); skipped when already inside code, links, etc. */
+function collectEmojiShortcodeRanges(text: string, merged: [number, number][]): [number, number][] {
+  const ranges: [number, number][] = []
+  const re = new RegExp(EMOJI_SHORT_CODE_REGEX.source, 'gu')
+  let m: RegExpExecArray | null
+  while ((m = re.exec(text)) !== null) {
+    const start = m.index
+    if (posInMerged(start, merged)) continue
+    ranges.push([start, start + m[0].length])
+  }
+  return ranges
+}
+
+/**
+ * Merged half-open ranges `[start,end)` in `text` that must be left unchanged for LT / translate.
+ */
+export function getMarkupProtectRanges(text: string, mode: AdvancedLabMarkupMode): [number, number][] {
+  const latex = collectLatexRanges(text)
+  const fenced = collectFencedCodeRanges(text)
+  let merged = mergeSortedRanges([...latex, ...fenced])
+
+  const wiki = collectWikiDoubleBracketRanges(text, merged)
+  merged = mergeSortedRanges([...merged, ...wiki])
+  const bookstrPass = collectBookstrMarkerPassthrough(text, merged)
+  const wikilinkM = collectWikilinkMarkerRanges(text, merged)
+  merged = mergeSortedRanges([...merged, ...bookstrPass, ...wikilinkM])
+  const linkMenu = collectLinkMenuColonMacros(text, merged)
+  merged = mergeSortedRanges([...merged, ...linkMenu])
+  const nostrBech = collectNostrAndBech32Ranges(text, merged)
+  merged = mergeSortedRanges([...merged, ...nostrBech])
+  const triplePlus = collectAsciiDocTriplePlusPassthrough(text, merged)
+  merged = mergeSortedRanges([...merged, ...triplePlus])
+
+  if (mode === 'markdown') {
+    const code = collectInlineCodeRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...code])
+    const links = collectMarkdownLinkImageStructureRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...links])
+    const fn = collectMarkdownFootnoteRefRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...fn])
+    const strike = collectMarkdownDelimiterPairEdges(text, merged, '~~')
+    const bold = collectMarkdownDelimiterPairEdges(text, mergeSortedRanges([...merged, ...strike]), '**')
+    const boldU = collectMarkdownDelimiterPairEdges(text, mergeSortedRanges([...merged, ...bold]), '__')
+    merged = mergeSortedRanges([...merged, ...strike, ...bold, ...boldU])
+  } else {
+    const adocBlocks = collectAsciiDocStructuredBlocks(text, merged)
+    merged = mergeSortedRanges([...merged, ...adocBlocks])
+    const code = collectInlineCodeRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...code])
+    const macros = collectAsciiDocInlineMacroRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...macros])
+    const xref = collectAsciiDocXrefRanges(text, merged)
+    merged = mergeSortedRanges([...merged, ...xref])
+  }
+
+  const prefixes = collectLinePrefixRanges(text, mode, merged)
+  merged = mergeSortedRanges([...merged, ...prefixes])
+  const pipes = collectPipeTableRanges(text, merged)
+  merged = mergeSortedRanges([...merged, ...pipes])
+  const emoji = collectEmojiShortcodeRanges(text, merged)
+  return mergeSortedRanges([...merged, ...emoji])
+}
+
+export function rangeIntersectsMerged(pos: number, len: number, merged: [number, number][]): boolean {
+  const a = pos
+  const b = pos + len
+  for (const [rs, re] of merged) {
+    if (a < re && b > rs) return true
+  }
+  return false
+}
+
+type Seg = { translatable: boolean; start: number; end: number }
+
+function buildSegments(text: string, merged: [number, number][]): Seg[] {
+  const segs: Seg[] = []
+  let cursor = 0
+  for (const [fs, fe] of merged) {
+    if (cursor < fs) segs.push({ translatable: true, start: cursor, end: fs })
+    if (fs < fe) segs.push({ translatable: false, start: fs, end: fe })
+    cursor = Math.max(cursor, fe)
+  }
+  if (cursor < text.length) segs.push({ translatable: true, start: cursor, end: text.length })
+  return segs
+}
+
+/**
+ * LibreTranslate often drops or normalizes newlines in `q`, which breaks Markdown/AsciiDoc.
+ * Split on line breaks (keep CRLF/LF as literal pieces) and only send non-whitespace text lines
+ * to the API; preserve newline runs and whitespace-only spans unchanged.
+ */
+async function translatePreservingLineBreaks(
+  text: string,
+  targetLang: string,
+  sourceLang: string
+): Promise<string> {
+  const pieces = text.split(/(\r?\n+)/)
+  const out: string[] = []
+  for (const p of pieces) {
+    if (p === '') continue
+    if (/^\r?\n+$/.test(p)) {
+      out.push(p)
+      continue
+    }
+    if (/^\s+$/.test(p)) {
+      out.push(p)
+      continue
+    }
+    out.push(await translatePlainText(p, targetLang, sourceLang))
+  }
+  return out.join('')
+}
+
+export async function translateAdvancedLabMarkup(
+  text: string,
+  targetLang: string,
+  sourceLang: string,
+  mode: AdvancedLabMarkupMode
+): Promise<string> {
+  const merged = getMarkupProtectRanges(text, mode)
+  if (merged.length === 0) {
+    return translatePreservingLineBreaks(text, targetLang, sourceLang)
+  }
+  const segs = buildSegments(text, merged)
+  const parts = await Promise.all(
+    segs.map(async (s) => {
+      const chunk = text.slice(s.start, s.end)
+      if (!s.translatable) return chunk
+      if (!chunk) return chunk
+      return translatePreservingLineBreaks(chunk, targetLang, sourceLang)
+    })
+  )
+  return parts.join('')
+}
diff --git a/src/lib/languagetool-cm-linter.ts b/src/lib/languagetool-cm-linter.ts
index d74680fe..e735365a 100644
--- a/src/lib/languagetool-cm-linter.ts
+++ b/src/lib/languagetool-cm-linter.ts
@@ -1,6 +1,11 @@
 import { linter, type Diagnostic } from '@codemirror/lint'
 import { Annotation, EditorSelection, type Extension } from '@codemirror/state'
 import type { EditorView } from '@codemirror/view'
+import {
+  getMarkupProtectRanges,
+  rangeIntersectsMerged,
+  type AdvancedLabMarkupMode
+} from '@/lib/advanced-lab-markup-protect'
 import { languageToolCheck, type LanguageToolMatch } from '@/lib/languagetool-client'
 
 /** Local LanguageTool is slow on cold JVM; keep payloads bounded (LT has ~20–30k limits anyway). */
@@ -76,8 +81,13 @@ function matchToDiagnostic(docLen: number, m: LanguageToolMatch): Diagnostic | n
  * Async grammar/style lint for CodeMirror using LanguageTool `/v2/check`.
  * Per-editor state (debounce / abort) lives in the closure so promises always settle and stale fetches are cancelled.
  * `getLanguage` is read on each lint pass so the UI can change language without remounting the editor.
+ * `getMarkupMode` selects which line-prefix syntax is treated as non-checkable markup.
  */
-export function languageToolLintExtension(getLanguage: () => string, debounceMs: number): Extension {
+export function languageToolLintExtension(
+  getLanguage: () => string,
+  debounceMs: number,
+  getMarkupMode: () => AdvancedLabMarkupMode
+): Extension {
   let requestSeq = 0
   let inFlight: AbortController | null = null
 
@@ -105,6 +115,8 @@ export function languageToolLintExtension(getLanguage: () => string, debounceMs:
         const ac = new AbortController()
         inFlight = ac
 
+        const protectMerged = getMarkupProtectRanges(toSend, getMarkupMode())
+
         void languageToolCheck(toSend, getLanguage(), ac.signal)
           .then((res) => {
             if (seq !== requestSeq) {
@@ -114,6 +126,7 @@ export function languageToolLintExtension(getLanguage: () => string, debounceMs:
             const docLen = view.state.doc.length
             const out: Diagnostic[] = []
             for (const m of res.matches ?? []) {
+              if (rangeIntersectsMerged(m.offset, m.length, protectMerged)) continue
               const d = matchToDiagnostic(docLen, m)
               if (d) out.push(d)
             }
diff --git a/src/lib/languagetool-language-order.test.ts b/src/lib/languagetool-language-order.test.ts
index 837dff8a..8606c87e 100644
--- a/src/lib/languagetool-language-order.test.ts
+++ b/src/lib/languagetool-language-order.test.ts
@@ -1,5 +1,24 @@
 import { describe, expect, it } from 'vitest'
-import { buildLanguageToolPreferenceList } from '@/lib/languagetool-language-order'
+import {
+  buildLanguageToolPreferenceList,
+  pickLanguageToolCodeForTranslateTarget,
+  translateTargetToLanguageToolCode
+} from '@/lib/languagetool-language-order'
+
+describe('translateTargetToLanguageToolCode', () => {
+  it('maps ISO codes to LT variants', () => {
+    expect(translateTargetToLanguageToolCode('ja')).toBe('ja-JP')
+    expect(translateTargetToLanguageToolCode('de')).toBe('de-DE')
+    expect(translateTargetToLanguageToolCode('zh-Hans')).toBe('zh-CN')
+  })
+})
+
+describe('pickLanguageToolCodeForTranslateTarget', () => {
+  it('returns mapped code when it appears in ltList', () => {
+    const lt = buildLanguageToolPreferenceList('en')
+    expect(pickLanguageToolCodeForTranslateTarget('ja', lt)).toBe('ja-JP')
+  })
+})
 
 describe('buildLanguageToolPreferenceList', () => {
   it('puts client language first then en-US then de-DE', () => {
diff --git a/src/lib/languagetool-language-order.ts b/src/lib/languagetool-language-order.ts
index 94691d20..c4c74f17 100644
--- a/src/lib/languagetool-language-order.ts
+++ b/src/lib/languagetool-language-order.ts
@@ -1,3 +1,5 @@
+import { normalizeTranslateLangCode } from '@/lib/translate-client'
+
 /**
  * Build LanguageTool `language` codes with UI language first, then English, then German, then others.
  * @see https://api.languagetool.org/v2/languages
@@ -114,6 +116,32 @@ function mapI18nToLt(i18nLanguage: string): string {
   return 'en-US'
 }
 
+/**
+ * Map a LibreTranslate / lab target language code to a LanguageTool `language` value
+ * (after {@link normalizeTranslateLangCode}).
+ */
+export function translateTargetToLanguageToolCode(translateCode: string): string {
+  const n = normalizeTranslateLangCode(translateCode).toLowerCase().replace(/_/gu, '-')
+  if (LT_ALIASES[n]) return LT_ALIASES[n]!
+  const base = n.split(/-/u)[0] ?? n
+  if (LT_ALIASES[base]) return LT_ALIASES[base]!
+  return 'en-US'
+}
+
+/** Prefer a code present in `ltList` (lab grammar dropdown) when possible. */
+export function pickLanguageToolCodeForTranslateTarget(
+  translateCode: string,
+  ltList: readonly string[]
+): string {
+  const mapped = translateTargetToLanguageToolCode(translateCode)
+  if (ltList.includes(mapped)) return mapped
+  const base = mapped.split(/-/u)[0]?.toLowerCase() ?? ''
+  const hit = ltList.find(
+    (c) => c.toLowerCase() === mapped.toLowerCase() || c.toLowerCase().startsWith(`${base}-`)
+  )
+  return hit ?? ltList[0] ?? mapped
+}
+
 export function buildLanguageToolPreferenceList(i18nLanguage: string | undefined): string[] {
   const primary = mapI18nToLt((i18nLanguage ?? 'en').trim() || 'en')
   const ordered: string[] = []