Does the notepad save on its own while I type?
Only if you turn on the local saving switch first. By default it is off and the text disappears when the tab closes; turned on, the current draft and up to 20 snapshots stay stored in the browser localStorage.
How many old versions does the history keep?
Up to 20 snapshots at a time. Saving the 21st drops the oldest one automatically, so the history behaves like a fixed-size queue and does not grow without bound inside the browser storage.
Can I import a large text file?
Yes, up to 2 MB per .txt file, which covers most drafts and meeting notes. Files above that cap are rejected before loading, so the notepad stays responsive even on weaker devices.