I apologize if this sort of PSA thing is not appropriate for this forum, but I didn’t see this announced in the February update, or in any other place on this forum. It is in the change notes on Github for 41.20250206, but I think a lot of users don’t regularly check those.
If you suddenly find that none of your Steam games will launch, as I did, check if you are using gamemoderun in the launch options and if so, see if removing it solves the problem. I got so used to adding “gamemoderun %command%” to solve performance issues over the years, that I automatically added it to every Steam game I downloaded and it didn’t even occur to me that it might be the problem, until several rebases and a Github visit later.
It’s a bit frustrating that this wasn’t announced more obviously (unless it was and I just completely missed it), but after setting Power Profile to performance and LACT to Manual → 3D_FULL_SCREEN I get pretty much the same performance (with maybe a bit more stuttering) so I can see why it would be removed.