Undo corrects then erases[ADDRESSED]

I was reading the Other Stuff page of the Tuto, and it explained about the asterisk thingy if the doc has been modified.

So I decided to experiment. I just cliqued in the page and taped a few random letters. When I found the asterisk, I undo’ed/CTRL+Z everything. I went a little too far, as it undo’ed only one letter at a time, instead of the last word I typed, and used one too many CTRL+Z: it erased the whole text on the Other Stuff page!

I tried opening another page and coming back to this one, undo’ing several times and redo’ing as well, nothing worked. The Other Stuff icon in the binder is blank, as if it were a new page. I can’t retrieve the text.

I believe that’s what the undo is meant to do?