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

This is my build of Proton with the most recent release of vanilla wine, has ffmpeg enabled for faudio by default, and all of Proton's patches ported over to be applied to wine, as well as wine-staging and vkd3d.

All patches:

-Warframe screenshot F6 patch -FFXIV Launcher patch -Mech Warrior online patch
-Assetto Corsa HUD patch -Vulkan child window patch
-sword art online gnutls patch
-d9vk integration
-vkd3d integration
-protonfixes integration
-FAudio with FFMpeg enabled (fixes audio/voices in multiple games)
-All of Valve's wine proton patches. Yes. All of them.
-wine staging patches
-various wine hot fixes for wine functionality that fix regressions per version

Change log:

This is a pre-release to fix the Warframe Launcher bug introduced in 2/18's update.

Download Proton 5.2-GE-1 from GitHub