- Enable live preview in Special:Preferences > Editing
- Visit new page, click [Create source] to create
- Enter lots of text, [Preview] many times
- Much later, wonder if you've saved your latest version yet, so click [Show changes]
Result: nothing is displayed, so you assume you've made no changes and quit your browser, and all your work is lost.
Expected result: please please do what regular [Show changes] does and display
Latest revision Your text Line 1: Line 1: (nothing) + lots of text + lots more text
so I know that I haven't actually saved the page yet.