Why are we doing this?
We currently do not warn contributors that their edits will be lost when they dismiss the editing mode, however this feature is present on web. It'd be great to show a standard alert that asks contributors if they want to discard their edits before closing the editor
Contributor story
As an editor I want to be warned before I close the editing mode if I have made modifications to the Wikitext
Proposed text
Header: Dismiss the editing mode?
Body: Are you sure you want to leave editing mode without publishing first?
Button (cancel): Cancel
Button (destructive): Discard edits