Markdown issue in 1Password for Mac

1. It only happened with one login item. I successfully got rid of any trace of it (sorry) but suffered with it for a long time before running into the discussion here and finally understanding how to get rid of it.
2. Yes, I tried copying the text while in edit view.
3. There was no markdown that I could see. It was that same huge/bold font in both normal and edit modes. Perhaps this had nothing to do with markdown at all and I just can't think of another reason why parts of a note would display that way? But the impression I get is that the note field is plaintext with the only control of fonts via markdown. Is it possible that the note field is rich text?
4. I didn't ever create a new item. I keep trying to repaste the original misformatted text back into the same item. Every paste simply retained the weird original formatting until I finally went the extra step of pasting it into another app (which doesn't support rich text) and copy/pasting it back into 1P.

The more I think about this, the more plausible it seems that it's not a markdown issue at all. Rather, somehow the Notes field supports rich text in yet another way that was never intended.