Hello @Ruedii, checking that Steam Linux Runtime - Soldier is downloaded as a runtime dependency is something that is managed by the Steam client, not Proton.
The Steam client should already be taking care of this, but it sounds like you've found a corner case where it gets missed. It would be helpful if someone figured out steps to reproduce the scenario starting with a Steam install that does not have any games set to use Proton 5.13+, Proton installed, or Steam Linux Runtime - Soldier installed.
checking that Steam Linux Runtime - Soldier is downloaded as a runtime dependency is something that is managed by the Steam client, not Proton
We should maybe transfer this to ValveSoftware/steam-for-linux rather than ValveSoftware/steam-runtime. The Steam Runtime is the library stack itself (including ~/.steam/root/ubuntu12_32/steam-runtime, "Steam Linux Runtime" and "Steam Linux Runtime - soldier"), but nothing in that stack has control over the circumstances under which the Steam client will decide to download one of the container runtimes.
Oh, sorry, this is already a steam-for-linux issue - ignore me, I haven't had enough coffee yet :-)
This problem is known to happen if adding a non-steam game, and then marking it as using Steam Play / Proton (or marking it as using the Steam for Linux runtime container). For non-steam games, the steam client does not perform dependency checks at this time.
Is this the case here? We have not been able to reproduce a failing/missing dependency check against store installed, "normal" Steam games. If you are able to cause this to happen with a Steam game, please let us know which, and provide the steam client logs + the compat log and content log (~/.steam/steam/logs/(compat,content)_log.txt).
No in this case it was switching a game from native to proton if I recall.
proton 5.13x1 2021-06proton 6.3x1 2021-06
With Proton 6.3 and other proton versions requiring Steam Runtime, the Steam client does not download Steam Runtime if it is not already installed.
When trying to run any game it gives "Cannot Set Up Runtime Due to Unspecified Error" which is hardly useful.
There should be a script that the first thing it runs is a check that Steam Runtime is properly installed and to message Steam to install it if it is not.