The editor discarded my changes

That happened when you left the editor without saving — and until 1.5.0.0 without any warning at all.

Since 1.5.0.0 it warns you on the way out if there are unsaved changes.

What is still missing: a visible marker in the page header that shows you while you work that something is unsaved. The warning on leaving exists, the marker is still on the list.

If you lose changes despite the warning, please post here with the mod version — then it is a bug and not a workflow.