tags plugin doesn't list un-tagged pages

The tags plugin used to list untagged pages. With the tags tab selected, the lower panel would list untagged pages as a special category, but it doesn't currently. (With the index tab selected, it might still list them but it's hard to tell.)
This might be 'expected' behavior, but if so, it's extremely poor from a UI standpoint. In fact, if unchanged, I will probably revert to an old zim release.