Easy Diablo 2 Resurrected dual-boxing with Steam on Linux
Since Proton / Wine automatically isolate file systems and processes from each prefix, on Steam adding (as a non-Steam game) the Battle.net app twice (and installing D2R with it, once for each account), allows dual-boxing without having to use any other apps or change any settings in the game or the launcher.
Step-by-step guide to this setup: https://leasys.baselinux.net/techdocs...
OS: Fedora 42
Proton version: 10.0
Note: Dual-boxing is not forbidden AFAIK and requires two Battle.net accounts and copies of the game.