I accidentally discovered a very simple way to reshow (most) hidden notes. It worked on 10 out of 11 notes that had gone missing in my title:
- Click on a page with a hidden note.
- Drag the divider between the title explorer or thumbnail view and the stage all the way to the left.
- You may also need to zoom all the way out to 25%; sometimes I did, sometimes I didn’t.
For 10 out of 11 notes, this revealed the note near the lower right corner of the stage, and I could easily drag it back to where I wanted it — and it stayed there when I dragged the divider back. I had to zoom out for two or three of them, not for the rest.
It’s still a silly bug that needs fixing, but at least this workaround is easier than editing the XML directly.