I've had a couple of customers recently let me know that some of the emails on their sites are coming back changed following a copy - specifically, being changed to thing@www.domain.com when they're using the www as their primary domain. From what I've found, it doesn't appear that there is a way to exclude certain things from this process, so we don't really have a way to resolve this aside from tell them they need to use the non-www as primary.

Ideally I feel like it would make sense to just exclude anything following an @ if possible, so emails don't get messed with during the search and replace. It's not coming up super frequently, though, even among customers using the www, so if it's already set up like that or something similar then this is a bug causing annoyance and confusion for customers.

Most recent impacted customer had already manually fixed the live site at the time of contact, but he sent me the attached screenshot of staging as an example which I suppose illustrates the point.