Hello,
I've created a hierarchy strictly following the manual at this page:
https://manual.calibre-ebook.com/sub_groups.html
I've added sub-categories and I can see the "Genre" hierarchy with its sub-categories in the tag browser.
However when clicking either at the top of the "genre" category or on any of its sub-category I can't cycles through 5 searches as described in the manual page.
It's either a simple green plus or simple red minus sign, all the others are not shown.
Is it something I've messed up or is it intended like this?