Valve have put out a fresh Proton Experimental upgrade for SteamOS / Linux systems, which thankfully includes a fix for the EA app breaking again. Only a few days ago Valve launched the new stable Proton 10.0-4, which Proton Experimental includes plus extra fixes not yet ready for everyone. See more on all the different Proton versions in the GamingOnLinux guide.

There were quite a lot of reports across social media, Reddit, and a few on Valve's official GitHub about various games published by EA (like Mass Effect) no longer launching due to issues with the EA app. This should now be solved with the latest update!