Feature Request: make auto saving optional

[lord-aerion]

Although the app has a manual save option, switching to view mode or backing out of the note results in any changes getting saved. This could lead to unwanted changes getting saved, with no way to undo them, other than restoring the previous state via the journal.

[lord-aerion]

Not quite sure how this would work with switching between edit and view mode to check whether the note renders as intended.

Would there be a way to generate a preview that doesn't actually save the note itself?