An updated version of the Steam Linux Runtime 4 branch was rolled out that has now shifted from Debian 11 to Debian 13 libraries for some significant upgrades. In the process more libraries have gone x86_64 only in foregoing the i386 builds. In addition, the SDL 2 library support for the Steam Runtime is now provided by sdl2-compat as the compatibility layer for SDL2 atop SDL3.
Valve and their partners at Collabora have rolled out a significant Steam Linux Runtime update to shift libraries from Debian 11 to Debian 13.2 after having skipped out on Debian 12. The approximate four year version jump has resulted in some libraries having a new SONAME for breaking ABI compatibility.
GTK, GLUT, FLTK, Qt, and others are all upgraded. SDL 2 using sdl2-compat is nice to see for enhancing support on modern Linux desktops by routing the old SDL2 usage through SDL3.
The release notes also mention that most libraries previously available for i386 and x86_64 have gone x86_64 only. Only i386 libraries that are expected ot be needed by Proton or other Steam tooling is kept. Long overdue and hopefully this leads to more Steam client x86_64 work.
More details on the updated Steam Linux Runtime update via SteamOS GitLab.
