The Online Tutorials section of InputMap in the editor's built-in
documentation viewer contains this link:
docs.godotengine.org/en/latest/tutorials/inputs/inputevent.html#inputmap
The macOS implementation for opening a link percent-encodes it before
sending it to the browser, resulting in a 404. This is to fix#13422
where filenames with special characters could not be opened in Finder.
However, this breaks URLS so I added a check to see if the resource
scheme is file:// and if so, only then is it escaped. This allows other
schemes like `http`, `ftp`, and `mailto` to be used.