Steam Linux Runtime

Introduced with proton 5.13-1 the Steam Linux Runtime is autostarted and part of the game command line parameters.

When stl is used as Launch Option both the Steam Linux Runtime and the [Proton Version](#Proton Selection) show up in the Steam Game launch command and therefore can be read by stl. In that case the Steam Linux Runtime can be disabled per game in the Game Config (f.e. via Game Menu) and if one (or more) of above confliciting tools are enabled stl warns that it is incompatible with the Steam Linux Runtime (for now).

When starting stl as Steam Compatibility Tool there are no Steam Linux Runtime parameters in the Steam Game launch command and therefore cannot be disabled (maybe comparable to the [Proton Version](#Proton Selection) which doesn't show up as command line parameter as well and is used 'under the hood').