I checked and I'm able to repro this on SteamOS 3.6 and 3.7. It seems like a Steam Client issue to me considering the CEF debugging tool suddenly disconnected while I was testing this and started the third step. Gamescope itself seems fine, and it even still thinks it's presenting frames if you move a mouse around and check gamescopectl backend_info. Restarting Steam or SDDM is also enough to recover from it.
Including my Steam device logs pulled from the devkit client in case it helps:
logs.zip
Issue is still not fixed after update to SteamOS 3.6.19 Stable
@matte-schwartz is restarting Steam can only be done via mouse and keyboard / SSH? No way to do this via gamepad keys? Thanks for collecting logs.
Don't think there's a shortcut for it, or at least none that I'm aware of. A fix will likely have to come from a Steam Client update rather than a SteamOS update.
Nothing extracted yet.
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