Steam recently updated their Chromium build to 72.0.3626.121
All the Chromium parts of Steam do not load anymore.
Starting Steam from the terminal shows
./steamwebhelper: error while loading shared libraries: libthai.so.0: cannot open shared object file: No such file or directory
I copied libthai.so.0 from an Ubuntu install to /usr/lib64 on Solus and then Steam gave the message that it needed libdatrie.so.1
I copied that over as well and now Steam on Solus is working.