Valve Software has just released another Proton update, which addresses regressions and resolves the garbage memory issue in generated libraryfolders.VDF files and restores on a best-effort basis.

Proton 10.0-1c (beta)

This is a very small bump fixing Proton 10.0 regressions.
For the main changelog see  https://github.com/ValveSoftware/Proton/releases/tag/proton-10.0-1b.

• Fixed issue where generated libraryfolders.vdf file had garbage memory written to it breaking software relying on it, e.g. mod launchers.
• Restored behavior that does best-effort Proton prefix upgrades when a unknown prefix version is detected.

Release Proton 10.0-1c (beta) · ValveSoftware/Proton