Thank you Ed,
I’m glad to hear that you don’t think this should be by design.
There was no error message. In this scenario the website and admin area are both completely blank. I looked at the source and want to say, though I don’t remember with 100% certainty, the source was empty too. Somehow a good response code was returned from the server but with no HTML? I was using Chrome by the way. I renamed the plug-in as a total guess, and it worked. Any of users who don’t have server access, at least immediately, would be very stuck!
It should be very easy to reproduce, just switch an Atelier site to Neighborhood without disabling the plugin first.
Thank you,
Terry