Strange. Discord, ProtonMail, ProtonUp-Qt, and Spotify should all work perfectly. Except maybe some drag and drop issues for Discord and ProtonMail? And Discord's activity status is blocked from tracking you. What issues did you have specifically?
I can see OpenRGB having issues given that tries to talk to the hardware itself, did you install the udev rules?
Handbrake has access to all your files by default so that shouldn't be an issue.
Heroic is really nice and what I recommend, but the UI is a bit clunky and spread out.