The Artboards panel menu showed Convert to Artboards disabled whatever
was selected, and choosing it did nothing, although Object › Artboards
› Convert to Artboards runs artboard.convertToArtboards on the
selection.
The panel menu's item now uses the same check as Object › Artboards ›
Convert to Artboards, so it is enabled when something is selected, and
it runs the same command. Each selected object that has an area becomes
a new artboard of its geometric bounds and is removed, in one undo step.
Docs: docs/target-app-parity.md.