Today I suddenly felt myself especially brave and stupid. That resulted in upgrade of my UM 22.04.5 LTS to 24.04.1 LTS in place using GUI.
All in all, the upgrade (per se) went very smoothly. Nevertheless, two dialogue windows made me to worry a bit. Those windows asked if I agree to upgrade and if I want to remove unnecessary packages. The problem with them was that <Cancel> and <Agree> buttons were way below the bottom of the (1600x900) screen and the windows could not be resized or moved to reveal those buttons. I had to blindly click on the question line and hit <Shift-Tab> and <Enter>.
As for the rest,
my vm.swappiness=10 setting was not preserved
systemd-resolved was reactivated with loopback dns stub
my custom theme was preserved
my custom keyboard layout was preserved
Kudos to developers and good luck to those who still puts off their upgrade!
That dialog box issue doesn't sound ideal. My guess is that the unnecessary packages could also be removed with a sudo apt autoremove after the install. Maybe.
That's right. Manifestation of the problem with oversized window was the same but the root cause, obviously, was different for the dialogue was not resizeable.
The problem: an oversized window can not be moved up because the window header can not cross the top of the screen. Drag by window's title bar does not work as well as Move invoked through the window's system menu.
There is an unexpected workaround, though. If one uses Movement Key, e.g. <Alt> for the case, then window can be moved up so, that its title bar goes above the top of the screen.
