I have previously not used the sorter, and decided to give it a go today and have it displayed as a “Dock Tab.” Currently I have one open database, and its favorites are visible in the sorter. However, the database as well as none of its groups are visible in the sorter under ‘Databases.’
The sorter opened with it collapsed and it took me until now to notice the icon to expand them, mostly because the icon doesn’t appear until one hovers over its location, which is hidden to a newbie who would have no idea that it existed; but I do now by serendipity. Maybe this is a reasonable thought regarding a future suggestion regarding development. Make the collapse icon “permanent.”