This should be reported to @anYc at https://github.com/anyc/steam-overlay.
Tele42, please review information i provided early.
Although i posted "hack" for gamerlay ebuild in Gentoo bug 531990 this issue must be fixed in Steam itself as mentioned by Gentoo dev Michał Górny.
I'm not using Steam overlay at all.
One more - by "user steam wrapper" i mean /usr/lib/steam/bootstraplinux_ubuntu12_32.tar.xz/steam.sh that unpacked to ~/.local/share/Steam/steam.sh
Yes, this is not something we can fix at our end. LD_LIBRARY_PATH is a big hammer, and even appending to the end still takes priority over the default system paths.
This also seems to break "optirun" since bumblebee add some library paths after /usr/lib32 apparently. I can no longer use "optirun" on my system, just "primusrun" (which add its paths on top of LD_LIBRARY_PATH).
Also the same root cause: https://github.com/ValveSoftware/steam-for-linux/issues/3851
With a last change to eselect-opengl in Gentoo there is new way of handling vendor-specific GPU drivers introduced. This is well explain in Gentoo bug 531842
However user steam wrapper - steam.sh - contains this lines:
That adds /usr/lib32 system path to LD_LIBRARY_PATH and make /usr/lib32 to take priority instead of those vendor specific in /etc/ld.so.conf.
This led to loading wrong libGL.so in Gentoo as described in bug 531990.
I think steam.sh must check distro before setting /usr/lib32 LD_LIBRARY_PATH and do it only if used in ubuntu linux.