fix: prevent FloatingFocusManager from resetting editor selection (#2525)

When FloatingFocusManager is used inside a FloatingPortal, floating-ui
inserts a hidden <span> after the domReference via insertAdjacentElement.
If the reference element is inside the ProseMirror contenteditable, this
triggers PM's MutationObserver and resets the editor selection.

Skip setting domReference when FloatingFocusManager is active and the
reference is within the editor DOM. Positioning still works via the
separate setPositionReference call.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: YousefED

packages/react/src/components/Popovers/GenericPopover.tsx

@@ -155,7 +155,18 @@ export const GenericPopover = (
       const element =
         "element" in props.reference ? props.reference.element : undefined;
 
-      if (element !== undefined) {
+      if (
+        element !== undefined &&
+        (props.focusManagerProps?.disabled !== false ||
+          !editor.isWithinEditor(element))
+      ) {
+        // Only set domReference when FloatingFocusManager is disabled.
+        // When FloatingFocusManager is active (disabled !== false) and the
+        // reference is inside the ProseMirror editor, setting domReference
+        // causes floating-ui to call insertAdjacentElement on the reference,
+        // inserting a focus-return <span> into the PM contenteditable. This
+        // triggers PM's MutationObserver and resets the editor selection.
+        // (issue #2525)
         refs.setReference(element);
       }
 
@@ -166,7 +177,7 @@ export const GenericPopover = (
         contextElement: element,
       });
     }
-  }, [props.reference, refs]);
+  }, [props.reference, refs, props.focusManagerProps?.disabled, editor]);
 
   // Stores the last rendered `innerHTML` of the popover while it was open. The
   // `innerHTML` is used while the popover is closing, as the React children

tests/src/end-to-end/ai/ai-selection.test.ts

@@ -0,0 +1,53 @@
+import { expect } from "@playwright/test";
+import { test } from "../../setup/setupScript.js";
+import { AI_URL } from "../../utils/const.js";
+import { focusOnEditor } from "../../utils/editor.js";
+
+const AI_BUTTON_SELECTOR = `[data-test="editwithAI"]`;
+
+test.beforeEach(async ({ page }) => {
+  await page.goto(AI_URL);
+});
+
+test.describe("AI toolbar button should preserve selection (issue #2525)", () => {
+  test("Editor selection must be preserved after clicking the AI toolbar button", async ({
+    page,
+  }) => {
+    await focusOnEditor(page);
+
+    // Select text in the first paragraph
+    await page.keyboard.press("Home");
+    await page.keyboard.press("Shift+End");
+    await page.waitForTimeout(500);
+
+    // Record the PM selection before clicking
+    const selBefore = await page.evaluate(() => {
+      const pm = (window as any).ProseMirror;
+      return { from: pm.state.selection.from, to: pm.state.selection.to };
+    });
+    expect(selBefore.to - selBefore.from).toBeGreaterThan(0);
+
+    // Click the AI button using page.mouse to trigger real browser
+    // focus-shift behavior (Playwright's locator.click() bypasses it)
+    const aiButton = page.locator(AI_BUTTON_SELECTOR);
+    await expect(aiButton).toBeVisible();
+    const box = (await aiButton.boundingBox())!;
+    await page.mouse.click(box.x + box.width / 2, box.y + box.height / 2);
+
+    // Wait for AI menu to appear
+    await page
+      .locator(".bn-combobox-input input, .bn-combobox input")
+      .waitFor({ state: "visible", timeout: 3000 });
+
+    // The PM selection must match what we had before clicking.
+    // Without the preventDefault fix on toolbar buttons, the browser
+    // moves focus to the portaled button on mousedown, which blurs the
+    // editor and clears the selection.
+    const selAfter = await page.evaluate(() => {
+      const pm = (window as any).ProseMirror;
+      return { from: pm.state.selection.from, to: pm.state.selection.to };
+    });
+    expect(selAfter.from).toBe(selBefore.from);
+    expect(selAfter.to).toBe(selBefore.to);
+  });
+});