@ddbb07 You're an absolute lifesaver - thanks!

@ddbb07 Thank you so much! That indeed worked! More correct here the full line for everyone:
WINEDLLOVERRIDES='winhttp=n,b' %command%

@Krzychu1245 The reason why patching with doorstop doesn't work by default using wine/proton is because wine overrides certain dlls to wine specific versions, this includes winhttp. This behaviour can be changed quite easily by either setting adding a rule in the winecfg progam or setting the environment variable WINEDLLOVERRIDES. This means that you could solve this by simply adding WINEDLLOVERRIDES='winhttp=n,b' to your steam launch options, this ensures that wine will try to load the doorstop winhttp.dll and only use the version built into wine as a fallback. Hope this is of help to someone! :)

@Sokrates I think you didn't understand the problem.
I'm not going to update the mod because there is nothing to update - newer version of internal library the mod is using doesn't solve any of known problems, plus it may break things for people who don't experience any issues.
In the last message I was talking about Proton - software compatibility layer that "simply" runs Windows game build on Linux machine but patching is not possible, that's why you have to use native build of the game (without Proton) and the guide applies only to the native build of the game.

Since you are not updating this mod, you should remove this, It is causing confusion

@Ronjoe I don't have more plans for this mod, things I tested, including migration to the latest possible version of loaded didn't change anything, it still doesn't work. I can do nothing.

Steam just forced my game to install Proton version instead of native Linux version. It might be necessary very soon to get that Wine/Proton support going.

Do note that if you have installed this mod, then moved your C:S installation to another disk (or other location), you may also need to update the path to the steam workshop folder manually in Cities_Loader.sh

@MRzoska that implies your game is installed in Steam installation directory (aka. default library folder) but you can have more and that is something I can't detect. If you want to use this and it works then no problem.

Would be easier to just make a launch argument bypassing the entire launcher
~/.steam/steam/steamapps/common/Cities_Skylines/Cities_Loader.sh %command%