Since Apple started code-signing Xcode with Xcode 9, Xcode plugins are no longer supported and it's recommended to use extensions
There are a few small, limited purposes for which they still work, including recognizing particular file types as tied to particular languages, which is what this plugin allows Xcode to do. However given x-code extensions seem to be the way forward to support iOS developers individual add-on / plugin needs, we'll consider if it's worthy to create an extension that offers similar functionality to what is available in this x-code plugin.
Since Apple started code-signing Xcode with Xcode 9, Xcode plugins are no longer supported and it's recommended to use extensions
There are a few small, limited purposes for which they still work, including recognizing particular file types as tied to particular languages, which is what this plugin allows Xcode to do. However given x-code extensions seem to be the way forward to support iOS developers individual add-on / plugin needs, we'll consider if it's worthy to create an extension that offers similar functionality to what is available in this x-code plugin.