There’s also Zen browser that’s Arc-like and based on Firefox instead of Chromium. Zen lets you sync tabs with Firefox elsewhere (including mobile Firefox), run the full uBlock Origin, and it is a fully open source browser.
It’s also available on Linux too (in addition to Windows and macOS), unlike Arc.
What’s the multi window feature in Chrome? Is that like containers in Firefox?
For the video problem, it might be codecs; try using Proton-GE if it’s in Steam or use Wine-GE if not. (IIRC, Steam will often convert the videos and give you the converted ones in the shader caching if necessary. But those outside of Steam, and sometimes a few still in Steam don’t have that workaround.)
For the main issue you’re having, try running those games in gamescope, which itself is a compositor with a bunch of neat tricks. In this case it’d make sure to not lose the focus of the game even if the gamescope window loses focus. It can also optionally force windowed or fullscreen modes, upscale (even with FSR1), and lock the framerate.
Changing settings in the game itself between fullscreen or borderless (borderless should usually help with the focus issues) may help too, if the game has that setting, but then you’ll probably hit the borders issue due to FVWM. (I don’t know if you’d get the fullscreen unredirection optimization in fvwm. That could be a reason to pick one or the other for you too.)
You’re probably hitting a few edge cases by using FVWM versus a more modern environment like GNOME or KDE, but to be fair I’ve seen the focus issue happen before on a game on running through Heroic on GNOME with more than one monitor before. FWIW: I don’t remember seeing the issue in games from Steam. (It probably depends on the game itself, however.)
If you’re in Europe, it may be due to the DMA.
You may also have noticed something new on Google, when looking for the address of a place: It’s now impossible to click on the map that appears in your search results.
Google is one of the “gatekeepers” according to the DMA (Digital Markets Act). The law recently went into effect. It is supposed to lessen the amount of preferential treatment the big tech companies give themselves.
Literally almost all of my and my partner’s friends and coworkers who are in Europe (including Germany, UK, Finland, Czechia, Greece, and more) have been sick with COVID in the past couple months to (especially) right now — it’s very real in Europe still.
People are all talking about COVID right now, in messages, emails, video calls, Mastodon, and more. (It’s usually to inform others that they’re sick and can’t work or meet up. But also complaining that doing basic stuff is difficult.)
Europe is a large place, of course, but at least in a lot of it, COVID is sadly still going strong.
You can even stream from the PS5 to the Deck too, thanks to Chiaki4Deck (easily installable on desktop mode from the “Discover” app).