Recording freezes after one frame of new window under ubuntu 20.04 but not with previous versions of ubuntu

[tatsujb]

I'm getting this bug where no matter what my setting for the input are the outputed video is only showing one frame of the fullscreen app in question (with the cursor still moving however and the sound still works) but in the video after each alt-tab the screen is frozen on that app, except for the cursor.

in the OBS preview, things look fine. on my screen, obviously, while I'm playing everything is nominal.
it's just when I open up the outputted mkv that I realize the issue.

Why is this happening. It should be noted that on this exact hardware (actually two different sets of hardware, a laptop and a desktop PC that have both had their OS replaced frequently) the bug did not occur for ubuntu 18.04, ubuntu 18.01.04, ubuntu 18.10, ubuntu 19.04 and ubuntu 19.10.

it is only on ubuntu 20.04 that I get this issue for both my laptop and my desktop PC.

Further context. I am recording a steam game that is emulated via proton (supreme commander, forged alliance to be exact). I don't get this bug if I window record a different app. but when I'm recording the whole screen in order to capture the game I'm talking about I now get this bug when in previous versions of ubuntu doing the exact same thing did not cause any issues.

Can anyone help me with this?

 

[tatsujb]

I figured it out! thanks to this : https://obsproject.com/forum/threads/solved-window-capture-black-screen.47082/

If I record as a window instead of the whole screen and select the running FA instance initially I would see a black screen in the preview. so initially I thought window recording wasn't possible.

but if you go to the next step you get this screen :

And you can enable the option called "alpha-less texture format (Mesa workaround)" (which makes sense because FA is a mesa app) then it works.

(I actually had to toggle on (then off because I don't actually want to swap colors) "Swap red and blue" to force it to apply.

there!