GloriousEggroll has released a new custom build of their Proton fork based on the latest Proton release.

Proton-5.11-GE-2-MF

This is a minor hotfix/stability release:

-Fixed issue with steam overlay causing mouse lag after 30+ minutes (issue present since 5.9, was missing from rawinput patches)
-Fixed issue with mouse hitting 'invisible walls' (issue present since 5.9, was missing from rawinput patches)
-Fixed issue with prefixes not generating properly causing some games not to be able to save due to the recent user name changes
-Ashes of the Singularity now works, vulkan renderer does not. Need to use DX11/12
-Jurassic World: Evolution now works

NOTE: If you want to allow your save games to work when using proton within lutris, you need to set WINEUSERNAME environment variable
NOTE: If you want proton's media foundation to work in lutris, you need to set GST_PLUGIN_SYSTEM_PATH_1_0 and WINE_GST_REGISTRY_DIR environment variables.

A full example is like this:

GST_PLUGIN_SYSTEM_PATH_1_0=/home/gloriouseggroll/.steam/steam/compatibilitytools.d/Proton-5.11-GE-2-MF/dist/lib64/gstreamer-1.0:/home/gloriouseggroll/.steam/steam/compatibilitytools.d/Proton-5.11-GE-2-MF/dist/lib/gstreamer-1.0

WINE_GST_REGISTRY_DIR=/home/gloriouseggroll/Games/origin/gstreamer-1.0/

WINEUSERNAME=gloriouseggroll

Download Proton 5.11-GE-2-MF from GitHub
Installation Instructions