TIL apparently the Mastodon Auto Share plugin for WordPress will happily toot "Loading, please wait ..." if for some reason that's still the text in the toot box because you only edited the post using text mode and not visual.
Yes, that's where that toot came from. (now deleted)
@skquinn I've been using Mastodon Autopost by L1am0; it's broken a few times on new versions, but right now it's stable.