Fix issue chat composer dropzone scope

ui/src/components/IssueChatThread.test.tsx

@@ -69,12 +69,14 @@ vi.mock("./MarkdownEditor", () => ({
     placeholder,
     className,
     contentClassName,
+    fileDropTarget,
   }: {
     value?: string;
     onChange?: (value: string) => void;
     placeholder?: string;
     className?: string;
     contentClassName?: string;
+    fileDropTarget?: "editor" | "parent";
   }, ref) => {
     useImperativeHandle(ref, () => ({
       focus: markdownEditorFocusMock,
@@ -85,6 +87,7 @@ vi.mock("./MarkdownEditor", () => ({
         aria-label="Issue chat editor"
         data-class-name={className}
         data-content-class-name={contentClassName}
+        data-file-drop-target={fileDropTarget}
         placeholder={placeholder}
         value={value}
         onChange={(event) => onChange?.(event.target.value)}
@@ -818,6 +821,7 @@ describe("IssueChatThread", () => {
     expect(editor?.dataset.contentClassName).toContain("max-h-[28dvh]");
     expect(editor?.dataset.contentClassName).toContain("overflow-y-auto");
     expect(editor?.dataset.contentClassName).not.toContain("min-h-[72px]");
+    expect(editor?.dataset.fileDropTarget).toBe("parent");
 
     act(() => {
       root.unmount();

ui/src/components/IssueChatThread.tsx

@@ -2254,6 +2254,7 @@ const IssueChatComposer = forwardRef<IssueChatComposerHandle, IssueChatComposerP
         mentions={mentions}
         onSubmit={handleSubmit}
         imageUploadHandler={onImageUpload}
+        fileDropTarget="parent"
         bordered={false}
         contentClassName="max-h-[28dvh] overflow-y-auto pr-1 text-sm scrollbar-auto-hide"
       />
@@ -2270,7 +2271,6 @@ const IssueChatComposer = forwardRef<IssueChatComposerHandle, IssueChatComposerP
             <input
               ref={attachInputRef}
               type="file"
-              accept="image/png,image/jpeg,image/webp,image/gif"
               className="hidden"
               onChange={handleAttachFile}
             />
@@ -2279,7 +2279,7 @@ const IssueChatComposer = forwardRef<IssueChatComposerHandle, IssueChatComposerP
               size="icon-sm"
               onClick={() => attachInputRef.current?.click()}
               disabled={attaching}
-              title="Attach image"
+              title="Attach file"
             >
               <Paperclip className="h-4 w-4" />
             </Button>

ui/src/components/MarkdownEditor.test.tsx

@@ -148,6 +148,17 @@ async function flush() {
   });
 }
 
+function createFileDragEvent(type: string) {
+  const event = new Event(type, { bubbles: true, cancelable: true }) as Event & {
+    dataTransfer: { types: string[]; files: File[]; dropEffect?: string };
+  };
+  event.dataTransfer = {
+    types: ["Files"],
+    files: [],
+  };
+  return event;
+}
+
 describe("MarkdownEditor", () => {
   let container: HTMLDivElement;
   let originalRangeRect: typeof Range.prototype.getBoundingClientRect;
@@ -319,6 +330,76 @@ describe("MarkdownEditor", () => {
       root.unmount();
     });
   });
+
+  it("shows the editor-scoped dropzone by default when files are dragged over it", async () => {
+    const root = createRoot(container);
+
+    await act(async () => {
+      root.render(
+        <MarkdownEditor
+          value=""
+          onChange={() => {}}
+          placeholder="Markdown body"
+          imageUploadHandler={async () => "https://example.com/image.png"}
+        />,
+      );
+    });
+
+    await flush();
+
+    const scope = container.querySelector('[data-testid="mdx-editor"]')?.parentElement as HTMLDivElement | null;
+    expect(scope).not.toBeNull();
+
+    act(() => {
+      scope?.dispatchEvent(createFileDragEvent("dragenter"));
+    });
+
+    expect(scope?.className).toContain("ring-1");
+    expect(container.textContent).toContain("Drop image to upload");
+
+    act(() => {
+      scope?.dispatchEvent(createFileDragEvent("dragleave"));
+    });
+
+    expect(scope?.className).not.toContain("ring-1");
+
+    await act(async () => {
+      root.unmount();
+    });
+  });
+
+  it("defers file-drop visuals to a parent container when requested", async () => {
+    const root = createRoot(container);
+
+    await act(async () => {
+      root.render(
+        <MarkdownEditor
+          value=""
+          onChange={() => {}}
+          placeholder="Markdown body"
+          imageUploadHandler={async () => "https://example.com/image.png"}
+          fileDropTarget="parent"
+        />,
+      );
+    });
+
+    await flush();
+
+    const scope = container.querySelector('[data-testid="mdx-editor"]')?.parentElement as HTMLDivElement | null;
+    expect(scope).not.toBeNull();
+
+    act(() => {
+      scope?.dispatchEvent(createFileDragEvent("dragenter"));
+    });
+
+    expect(scope?.className).not.toContain("ring-1");
+    expect(container.textContent).not.toContain("Drop image to upload");
+
+    await act(async () => {
+      root.unmount();
+    });
+  });
+
   it("anchors the mention menu inside the visual viewport when mobile offsets are present", () => {
     expect(
       computeMentionMenuPosition(

ui/src/components/MarkdownEditor.tsx

@@ -68,6 +68,8 @@ interface MarkdownEditorProps {
   imageUploadHandler?: (file: File) => Promise<string>;
   /** Called when a non-image file is dropped onto the editor (e.g. .zip). */
   onDropFile?: (file: File) => Promise<void>;
+  /** When set to `parent`, a wrapper owns drag/drop behavior and visuals. */
+  fileDropTarget?: "editor" | "parent";
   bordered?: boolean;
   /** List of mentionable entities. Enables @-mention autocomplete. */
   mentions?: MentionOption[];
@@ -491,6 +493,7 @@ export const MarkdownEditor = forwardRef<MarkdownEditorRef, MarkdownEditorProps>
   onBlur,
   imageUploadHandler,
   onDropFile,
+  fileDropTarget = "editor",
   bordered = true,
   mentions,
   onSubmit,
@@ -897,8 +900,7 @@ export const MarkdownEditor = forwardRef<MarkdownEditorRef, MarkdownEditorProps>
     return Array.from(evt.dataTransfer?.types ?? []).includes("Files");
   }
 
-  const canDropImage = Boolean(imageUploadHandler);
-  const canDropFile = Boolean(imageUploadHandler || onDropFile);
+  const canDropFile = fileDropTarget === "editor" && Boolean(imageUploadHandler || onDropFile);
   const handlePasteCapture = useCallback((event: ClipboardEvent<HTMLDivElement>) => {
     const clipboard = event.clipboardData;
     if (!clipboard || !ref.current) return;