Steam client version (build number or date): Jul 12 2021, at 21:00:39
Distribution (e.g. Ubuntu): Gentoo
Opted into Steam client beta?: [Yes/No] Yes
Have you checked for system updates?: [Yes/No] Yes
Please describe your issue in as much detail as possible:
For game mods, like Deus Ex: Revision (https://steamdb.info/app/397550/) for example, if you download the original Deus Ex and install it (https://steamdb.info/app/6910/), the Revision mod will have a green "INSTALL NOW", but not actually be installable.
When a Windows only game doesnt have proton compatibility enabled, the "INSTALL NOW" button is greyed. But since this is a mod, it must bug the UI, and make the "INSTALL NOW" button green, even though proton compatibility isnt actually enabled on it.
This definitely is a UI bug with mods, since the green "INSTALL NOW" button should only be green when proton compatibility is enabled on the game, just like other Windows only games behave.
EDIT:
I must also mention that I do not have "enable steam play for all titles" enabled and ticked under steam settings.
Steps for reproducing this issue:
Install original Deus Ex
Try to install Revision, with the INSTALL NOW button green
It doesnt actually let you install it until you enable proton compatibility
the button shouldnt be green in the first place since proton compatibility is not enabled on the mod, as this is how all other windows games behave
Your system information
Please describe your issue in as much detail as possible:
For game mods, like Deus Ex: Revision (https://steamdb.info/app/397550/) for example, if you download the original Deus Ex and install it (https://steamdb.info/app/6910/), the Revision mod will have a green "INSTALL NOW", but not actually be installable.
https://github.com/ValveSoftware/Proton/issues/4958#issuecomment-878457955
When a Windows only game doesnt have proton compatibility enabled, the "INSTALL NOW" button is greyed. But since this is a mod, it must bug the UI, and make the "INSTALL NOW" button green, even though proton compatibility isnt actually enabled on it.
This definitely is a UI bug with mods, since the green "INSTALL NOW" button should only be green when proton compatibility is enabled on the game, just like other Windows only games behave.
EDIT:
I must also mention that I do not have "enable steam play for all titles" enabled and ticked under steam settings.
Steps for reproducing this issue: