I've seen this a few times where parameters that are not being modified get the warning incorrectly, here is one example. It appears to believe that there is an assignment to __instance.Sheet and __instance.Key (which is not the case) and that doing so requires it to be a ref parameter (which is also not the case)
https://github.com/silksong-modding/Silksong.I18N/blob/bb7576ab3af7c76da12948dd897dee1875972c11/I18NPlugin.cs#L178
I've seen this a few times where parameters that are not being modified get the warning incorrectly, here is one example. It appears to believe that there is an assignment to
__instance.Sheetand__instance.Key(which is not the case) and that doing so requires it to be a ref parameter (which is also not the case)https://github.com/silksong-modding/Silksong.I18N/blob/bb7576ab3af7c76da12948dd897dee1875972c11/I18NPlugin.cs#L178