I'm sure you're wondering why the hell I'd want to do that. I'd like to run a Steam game (Doom 3 to be specific), and I can force it to download since Steam now uses Proton to be compatible, but I want to be able to use the community source port instead, which uses a native Linux executable, while still logging my hours in Steam. So, I downloaded Doom 3 from Steam, then copied the files from the source port. Steam, however, can only point to "Doom3.exe", and there's no option in Kubuntu to disconnect the file name from the file type, so renaming the source port's executable to Doom3.exe and launching from Steam does not work, with it attempting to launch it as a Windows executable. I did find a "File Type Options" in the properties for the file, but the "*.exe" entry comes back immediately after removal. I'm hoping I can write a script of some sort to make this work, and I'd appreciate any help I could be given. Of course I can just play it without Steam, but I'd very much like to have my hours counted.