SUMMARY I'm using a third-party cursor theme called 'Future Cursors' and Firefox 104. STEPS TO REPRODUCE 1. use Wayland session 2. run Firefox - I can reproduce regardless Firefox runs natively on Wayland or on Xwayland 3. activate the menu bar by pressing alt key 4. hover over any menu and make sure the mouse pointer is touching the screen edge 5. click OBSERVED RESULT the menu bar closes EXPECTED RESULT clicked menu opens SOFTWARE/OS VERSIONS Operating System: KDE neon Unstable Edition KDE Plasma Version: 5.26.80 KDE Frameworks Version: 5.99.0 Qt Version: 5.15.6 Graphics Platform: Wayland
Ops, can reproduce on X11 too. We must maximize Firefox after opening it.
How did it use to work in 5.25?
As far as I can tell, this is a Firefox bug. With CSD mode and the menubar shown, the menu items don't actually touch the top-most pixel of the screen. So when you click that top-most pixel, you're clicking in an empty area of the menu toolbar, so it hides the menu toolbar--just like when you click in any other empty part of the menu toolbar.