Firefox based browsers don’t as far as I know support protocols direct to usb connections, so if you’re using a web app based application (for example, some keyboard software) to flash your layouts you need a chromium based browser, and people generally choose brave over chrome (though I think it would be 100% fine to use chromium with hardening but that’s difficult with some of the upstream changes making chrome extension store less helpful — built in mitigations upstream as found in brave may be helpful in this regard, and faster).
Probably nothing (because your gpu has some power spikes, just not hitting max power), but I’d make sure the integrated gpu in the bios is turned off; it’s possible something happened when playing, and the bios reverted to selecting the igpu on your 7900x3d. When I first booted my 7800x3d this was occurring, and I fixed it by turning it off in the bios.