Ignore read-only editors for side menu targeting

packages/core/src/extensions/SideMenu/SideMenu.ts

@@ -324,8 +324,13 @@ export class SideMenuView<
     clientX: number;
     clientY: number;
   }) => {
-    // Get all editor elements in the document
-    const editors = Array.from(this.pmView.root.querySelectorAll(".bn-editor"));
+    // Read-only editors cannot show a side menu or accept a dropped block, so
+    // they must not compete with editable editors that overlap them.
+    const editors = Array.from(
+      this.pmView.root.querySelectorAll(
+        '.bn-editor:not([contenteditable="false"])',
+      ),
+    );
 
     if (editors.length === 0) {
       return null;

tests/src/end-to-end/draghandle/overlappingEditors.test.tsx

@@ -0,0 +1,38 @@
+import "@blocknote/core/fonts/inter.css";
+import { BlockNoteView } from "@blocknote/mantine";
+import "@blocknote/mantine/style.css";
+import { useCreateBlockNote } from "@blocknote/react";
+import { describe, test } from "vite-plus/test";
+import { render } from "vitest-browser-react";
+import { DRAG_HANDLE_SELECTOR } from "../../utils/const.js";
+import { waitForSelector } from "../../utils/editor.js";
+import { moveMouseOverElement } from "../../utils/mouse.js";
+
+function OverlappingEditors() {
+  const readOnlyEditor = useCreateBlockNote();
+  const editableEditor = useCreateBlockNote();
+
+  return (
+    <div style={{ display: "grid" }}>
+      <div style={{ gridArea: "1 / 1" }}>
+        <BlockNoteView editor={readOnlyEditor} editable={false} />
+      </div>
+      <div style={{ gridArea: "1 / 1", zIndex: 1 }}>
+        <BlockNoteView editor={editableEditor} />
+      </div>
+    </div>
+  );
+}
+
+describe("Overlapping editors", () => {
+  test("shows the side menu for an editable editor over a read-only editor", async () => {
+    await render(<OverlappingEditors />);
+
+    const editableBlock = await waitForSelector(
+      '.bn-editor[contenteditable="true"] [data-content-type="paragraph"]',
+    );
+    await moveMouseOverElement(editableBlock);
+
+    await waitForSelector(DRAG_HANDLE_SELECTOR);
+  });
+});