When i press the "play" button nothing happens . If you run it in a terminal with the -steam flag, then this error is found:
libGL error: MESA-LOADER: failed to open radeonsi: /home/azrabrijer/.local/share/Steam/steamapps/common/Thinking with Time Machine/bin/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /usr/lib32/dri/radeonsi_dri.so) (search paths /usr/lib32/dri, suffix _dri)
libGL error: failed to load driver: radeonsi
libGL error: MESA-LOADER: failed to open swrast: /home/azrabrijer/.local/share/Steam/steamapps/common/Thinking with Time Machine/bin/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /usr/lib32/dri/swrast_dri.so) (search paths /usr/lib32/dri, suffix _dri)
libGL error: failed to load driver: swrast
X Error of failed request: BadValue (integer parameter out of range for operation)
Major opcode of failed request: 150 (GLX)
Minor opcode of failed request: 3 (X_GLXCreateContext)
Value in failed request: 0x0
Serial number of failed request: 81
Current serial number in output stream: 82
P.S.I tried to verify the cache, it did not help, portal 2 is installed.