Well. That was an adventure.
I was messing with my machine, trying to work out why the bottom tension was a bit off, and I noticed the feed dog drop switch wasn’t making the feed dog come back up again… that’s no good. I need the feed dog up.
So I went on YouTube, found some very very very helpful videos, and stripped my machine back to bare bones. Only to find on closer inspection that there was literally no problem, it’s just that the offset cam was in the down position while I was flipping the switch. If I turned it to the up position, the feed dog came up as expected. Well, that was a half day wasted.
I learned a lot about my machine though. Sigh.