message: Add tooltip to Upload Attachments button
diff: @@ -17,7 +17,7 @@ async function addButtons() {
  const toolbarGroup = select('.toolbar-group:last-child', toolbar);
  if (toolbarGroup) {
  toolbarGroup.append(
  - <button type="button" class="toolbar-item rgh-upload-btn">
  + <button type="button" class="toolbar-item rgh-upload-btn tooltipped tooltipped-nw" aria-label="Upload attachments">
  {icons.cloudUpload()}
  </button>
  );
  