12-18-2022, 12:33 PM -
I'm having this issue on my desktop as well (Endeavour with KDE Plasma, somewhat similar to Steam Deck) so I'm going to assume this is rather KDE related, especially since it's confirmed to not be an issue on Gnome.
A temporary solution for me was to an "Application menu" button to my Titlebar, under the Window Decorations -> Titlebar Buttons settings.
This added a Hamburger menu in my titlebar from which I would get a dropdown with the usual File, Emulation, Configuration ...
As suggested in this Reddit thread (https://www.reddit.com/r/kde/comments/z1..._menu_bar/), I tried turning off the "Application menus daemon" under Background Services.
This made my RPCS3 menu re-appear.
A temporary solution for me was to an "Application menu" button to my Titlebar, under the Window Decorations -> Titlebar Buttons settings.
This added a Hamburger menu in my titlebar from which I would get a dropdown with the usual File, Emulation, Configuration ...
As suggested in this Reddit thread (https://www.reddit.com/r/kde/comments/z1..._menu_bar/), I tried turning off the "Application menus daemon" under Background Services.
This made my RPCS3 menu re-appear.