js/desktop/src/hooks/use-file-input.ts

@@ -5,6 +5,19 @@ interface UseFileInputOptions {
   enabled: boolean;
 }
 
+/**
+ * Files carried by a paste. A pasted image is usually exposed only through
+ * `items` (`getAsFile`), with `files` left empty, so read `items` first and
+ * fall back to `files` for the rare clipboard that populates only the latter.
+ */
+function clipboardFiles(data: DataTransfer): File[] {
+  const fromItems = Array.from(data.items)
+    .filter((item) => item.kind === 'file')
+    .map((item) => item.getAsFile())
+    .filter((file): file is File => file !== null);
+  return fromItems.length > 0 ? fromItems : Array.from(data.files);
+}
+
 export function useFileInput({
   onFilesSelected,
   enabled,
@@ -49,14 +62,20 @@ export function useFileInput({
     if (!enabled) return;
 
     // Capture phase so file pastes always become attachments — ProseMirror
-    // would otherwise inline pasted images as ephemeral blob: URLs. Mixed
-    // clipboards (e.g. Excel/Word ship an image rendition alongside the text)
-    // must still paste as text, so only file-only pastes are intercepted.
+    // (the markdown editor) would otherwise inline a pasted image as an
+    // ephemeral blob: URL and get stuck on its "uploading" placeholder.
     const handlePaste = (e: ClipboardEvent) => {
       const data = e.clipboardData;
       if (!data) return;
-      const files = Array.from(data.files);
-      if (files.length === 0 || data.types.includes('text/plain')) return;
+
+      // Actual text means "paste as text", even when the clipboard also ships
+      // an image rendition (Excel/Word, or "copy image" from a page with alt
+      // text). Test the payload, not the advertised types: image pastes often
+      // list an *empty* text/plain entry that must not block the attachment.
+      if (data.getData('text/plain').trim().length > 0) return;
+
+      const files = clipboardFiles(data);
+      if (files.length === 0) return;
       e.preventDefault();
       e.stopPropagation();
       onFilesRef.current(files);