Hello @aumars, what CPU is in your system?
Intel Core 2 Quad Q6600
This is an Arch packaging issue for lib32-mesa being tracked at https://bugs.archlinux.org/task/58697. As this is an issue outside of Steam, there won't be much more activity here.
Reverting to lib32-mesa-18.0.4-2 should workaround this issue until it is resolved by the package maintainer.
I updated lib32-mesa to lib32-mesa-18.1.2-2 . The issue is fixed.
Closing per the last comment.
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
Restarting my machine did not help. The only thing I haven't tried is reinstalling the Steam client.
Steps for reproducing this issue:
steamas user using a terminal.