fix post editor

src/components/PostEditor/PostContent.tsx

@@ -3379,7 +3379,7 @@ export default function PostContent({
         </div>
       )}
       
-      <div className={cn(isSmallScreen && 'flex min-h-0 min-w-0 flex-1 flex-col')}>
+      <div className={cn(isSmallScreen && 'flex min-h-0 min-w-0 flex-1 flex-col overflow-hidden')}>
       <PostTextarea
           ref={textareaRef}
           text={text}
@@ -3391,7 +3391,7 @@ export default function PostContent({
             isPoll
               ? 'min-h-20'
               : isSmallScreen
-                ? 'min-h-[min(42vh,20rem)]'
+                ? 'min-h-0'
                 : 'min-h-52',
             isDiscussionThread && threadErrors.content && 'border-destructive'
           )}

src/components/PostEditor/PostTextarea/index.tsx

@@ -180,9 +180,10 @@ const PostTextarea = forwardRef<
       () =>
         cn(
           'border rounded-lg p-3 focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring',
+          isSmallScreen && 'min-h-0 flex-1 overflow-y-auto overscroll-y-contain',
           className
         ),
-      [className]
+      [className, isSmallScreen]
     )
 
     const editor = useEditor({
@@ -325,7 +326,7 @@ const PostTextarea = forwardRef<
         value={activeTab}
         onValueChange={setActiveTab}
         className={cn(
-          isSmallScreen ? 'flex min-h-0 flex-1 flex-col gap-2' : 'space-y-2'
+          isSmallScreen ? 'flex min-h-0 flex-1 flex-col gap-2 overflow-hidden' : 'space-y-2'
         )}
       >
         <div className="flex min-w-0 shrink-0 flex-col gap-2">
@@ -348,12 +349,15 @@ const PostTextarea = forwardRef<
           forceMount
           className={cn(
             'mt-0 data-[state=inactive]:hidden focus-visible:ring-0 focus-visible:ring-offset-0',
-            isSmallScreen && 'flex min-h-0 flex-1 flex-col'
+            isSmallScreen && 'flex min-h-0 flex-1 flex-col overflow-hidden'
           )}
         >
           {editor ? (
             <EditorContent
-              className={cn('tiptap', isSmallScreen && 'flex min-h-0 flex-1 flex-col')}
+              className={cn(
+                'tiptap',
+                isSmallScreen && 'flex min-h-0 flex-1 flex-col overflow-hidden'
+              )}
               editor={editor}
             />
           ) : (

src/index.css

@@ -103,8 +103,17 @@
   }
 
   @media (max-width: 768px) {
-    .tiptap .ProseMirror {
-      min-height: min(42vh, 20rem);
+    /* Mobile composer: scroll inside the bordered editor instead of painting past it. */
+    .tiptap.flex-col {
+      min-height: 0;
+    }
+    .tiptap.flex-col .ProseMirror {
+      min-height: 0;
+      max-height: 100%;
+      overflow-y: auto;
+      overscroll-behavior-y: contain;
+      -webkit-overflow-scrolling: touch;
+      overflow-wrap: anywhere;
     }
   }