Not sure if this is this plugin (but think it is)
Describing previous behaviour
When you plugin a Kobo device a pop up appears to update reading position/%read. You can select which books to include in that update.
After that (maybe this part isn't this plugin?) another popup to update to goodreads, your progress.
Asking here as this plugin updated around the same time Calibre did, and a week or so after the goodreads plugin, so hard to know what's what (for me, LOL).
Now on plugin, neither pop up appears.
This is with a Kobo Clara HD.
If the wrong, I'll happily post where appropriate