I don’t think its really a very strong rule tbh, if it is one. I’m a native english speaker and I hear people say if before would all the time.
In the sentence in question, “were to” would probably work better, but mainly as would had already been used earlier, and it feels clunky repeating it.
“If you would do x for me, that’d be great.” Good example of an if before a would.
It might be a good idea to remove r/steamdeck_linux from the list. I restricted that subreddit a while ago, and this community serves as it's replacement.
oh dear. hmm. dunno what to do to fix that tbh.