Pop-up windows dissapear immediately [solved]

I have just started learning Unity 3d, and have run into an odd issue with pop-up windows:

On the game tab, if I select the resolution/aspect ratio drop down menu on the upper left and click "+", the pop-up window appears for a fraction of a second and this disappears.

Something similar seems to happen if I try changing the background color for the main camera, but the color picker window only disappears if I try to move the window.

I run the appimage in the terminal, but it doesn't seem to provide any useful data on the issue. Neither does JournalCTL. Any help would be greatly appreciated. I am running 2019.4.1f1, though I tried 2020.1.0b15 and that didn't make a difference.

Here is a pastebin of my system data: https://paste.ubuntu.com/p/KqBZfHZ3Yh/

 

So...it turns out that I never created a project using 2020.1.0b15. When I figured that out, I created a project in 2020.1.0b15 and it solved my problem. Hopefully my mistake will help someone else.

 

Been getting this with 2019.4.1f1 since updating from 2019.3.0f3. Particularly annoying with the colour picker, as it also usually opens half off the screen. Given 2019.4.1f1 is supposed to be LTS, I'm not happy about the prospect of migrating to 2020.x for a fix.