カテゴリフィルターで「なし」から「すべて」への切り替えが機能しない

This suddenly stopped working for me today, and I’m not quite sure why, so I’m not ready to report it as a bug just yet.

I have my top-level categories’ Default List Filter set as no subcategories" but want to occasionally check all at once to clear out new posts once in a while. When I switch to all, it refreshes as it’s supposed to, but doesn’t show the “all” list.

Click for gif screenshot