It does work in Proton, but without audio.
There’s a bug open @ https://github.com/ValveSoftware/Proton/issues/7612
ProtonDB also lists the lack of audio, without workarounds (so far): https://www.protondb.com/app/2512840?device=any
Hopefully there will be a fix and/or workaround very soon; the game looks fun.
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.
https://zen-browser.app/
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?