[dev-v5] AppBar Overflow menu does not open in RC5

🐛 Bug Report

The FluentAppBar overflow menu does not open in RC5.

💻 Repro or Code Sample

A ready-to-run reproduction is available here:

https://github.com/matteoparlato/AppBarRepro1

The repro contains a horizontal FluentAppBar with a large number of
FluentAppBarItem elements, causing some items to be collapsed into the
overflow menu.

Steps to reproduce

1. Clone the repository:
   https://github.com/matteoparlato/AppBarRepro1
2. Run the application.
3. Resize the browser window so that the FluentAppBar cannot display all
   the items.
4. The overflow (...) button is displayed.
5. Click the overflow (...) button.

🤔 Expected Behavior

Clicking the overflow (...) button should open the overflow menu/popover
and display the FluentAppBarItem elements that were collapsed because
there was not enough space.

This works correctly in RC4.

😯 Current Behavior

In RC5, the overflow (...) button is displayed, but clicking it does not
open the overflow menu/popover.

The collapsed FluentAppBarItem elements are therefore not accessible.

This appears to be a regression introduced in RC5.

💁 Possible Solution

I don't have a proposed fix at this time.

The overflow button itself is rendered correctly, so the issue seems to be
related to the opening/rendering of the overflow menu or popover when the
button is clicked.

🔦 Context

We use FluentAppBar as a navigation/action bar with a dynamic number of
items.

The overflow functionality is important because it allows items that do
not fit in the available space to remain accessible.

The behavior worked correctly in RC4. After upgrading to RC5, the overflow
button is still displayed, but the menu containing the collapsed actions
no longer opens.

🌍 Your Environment

OS & Device: Microsoft Windows 10.0.26200 (X64)
Browser: Microsoft Edge / Google Chrome
.NET and Fluent UI Blazor library Version: .NET 10.0.11 / Fluent UI Blazor RC5 5.0.0-rc.5-26219.1