@sgunhouse Hi, thank you for responding.
I always play with Opera open, listening to music on YouTube. I don't usually have many tabs open, at most 3, and I have 3 pinned tabs. But I noticed that even without any game open, sometimes just opening Opera, it already closes Steam.
I tried clearing the browsing data, and apparently, since yesterday, the problem has been resolved. I also scanned the PC with the antivirus to see if there was anything, but it didn't find anything.

Hi, for the past few days, my browser has been closing, and with it, everything else that's open also closes (games, other browsers, Steam, Discord, etc.). Has anyone else experienced this?