GodotSteam

The standard version of Godot doesn't have native support for the Steam SDK. This means that, if the game you're editing has Steam support, it probably won't run. To solve this, use a modified version of the Godot editor called GodotSteam.

You'll want to get the GodotSteam release version that matches your game's version (eg. Godot 3.5 is here). Also note that GodotSteam comes as a GDNative/GDExtension plugin version - both work, but the full pre-compiled editor is simpler to get running.

You will usually be able to get the Godot version from the gdre export log, and you can usually take the newest GodotSteam version that supports it. To get the exact version you will usually have to ask the game developer - and sometimes the modding guide for each game will tell you.