Well, I’m on a Mac, so F12 doesn’t work that way…
But since you mentioned deactivating plugins, I tried turning off Dagon Design Form Mailer and, as I suspected, that seems to be the culprit.
I think it’s because I’ve been using DDFM for the weekly quiz on my site, so I’m adding a new form every week. This problem had been occurring a little before, but yesterday when I added instances (going from 430 instances to 450) so I’d have blank records to fill in over future weeks, it suddenly got worse. And subtracting instances made the problem a little less severe again.
I think the plugin wasn’t built to have so many instances set up, or it sets off a bit of a bug or something. I wrote to the maker right after I first posted here, but as I recall they don’t have a great track record of responding — I think it’s just like one or two guys.
I’d like to delete old instances, but it appears to me that all you can do is increase or decrease the number of instances (thus, decreasing would delete the NEWEST instances) rather than selecting and deleting specific ones.
Maybe I need to find a different plugin for this? The site is Machigai.com, where I put up a quiz every Wednesday.