Ok, so it looks like MEC 7.30.0 is breaking things (see WP support link). 7.30.1 is out, but I can’t update to it. I tried deleting and reinstalling the plugin from Pro, but it was the 7.30 version. I’m wondering if you can somehow provide a download for 7.29. Cheers!
EDIT TO ADD: Ok I was able to get version 7.29 from another site’s files. But I guess, FYI this seems to be an issue I assume you want to know about.