I created a new equation. It had a blank paragraph after it. I position my cursor on the blank line. I hit command-delete to remove the blank paragraph. It deletes the blank line AND the equation above it.
Using a command-Z to undo the mistake undoes the a deletion that I made BEFORE deleting the paragraph (and the equation).
- command-delete deletes too much
- the undo buffer does not capture the command to allow it to be undone