As for restricting access to files you could run them under a separate user account. User A shouldn’t have access to User B’s home folder. Although if its something that would need granted admin access I think it would have access to other users files again.

KDE does have focus stealing prevention, Have you messed with that at all? https://docs.kde.org/stable5/en/kwin/kcontrol/windowbehaviour/index.html#focus-focusstealing The only thing I can think of is maybe some notification steals the focus and doesnt give it back to the window.

This is a good page to check out if you’re in the market for a new device https://github.com/melontini/bootloader-unlock-wall-of-shame

I have a x1 carbon gen 9. Be very careful with the USB-C ports. I leave mine on my desk and my hub kept cutting in and out while using it and its gotten worse over time. I’ve seen others with similar issues and it seems like the fix is to solder on a new port. Its a work laptop so I just deal with it.

This happens on my Pixel as well. I forget which launcher I use but I keep the icon on my homescreen so I can just hold it to get the app info and force stop it.

Do they support port forwarding?