Steam launcher crashes sometimes, and according to /home/USERNAME/.local/share/Steam/logs/console-linux.txt this error might be caused by Artix-dark theme:
...
/usr/share/themes/Artix-dark/gtk-2.0/gtkrc:1218: error: unexpected identifier 'direction', expected character '}'
/usr/share/themes/Artix-dark/gtk-2.0/gtkrc:1218: error: unexpected identifier 'direction', expected character '}'
/home/USERNAME/.local/share/Steam/steam.sh: line 978: 16632 Segmentation fault "$STEAMROOT/$STEAMEXEPATH" "$@"
This usually happens when Steam is launched from a Desktop shortcut, don't know why but it's Exec string - if copied to a Terminal and launched from there, usually works. Menubar shortcut also seem to be working, despite it having the same Exec string. Full console-linux.txt log is attached below
This is very hard to debug, it's triggered by the "combobox_entry" style running on the pixmap engine, i.e. go figure.