[Bug] Filters/View controls disappear from music library in Tracks view

Attempting to create a Smart Collection or Smart Playlist also exhibits the behavior:
Create Smart Collection / Playlist not working

Reloading the page does restore the button toolbar, but it also cancels the creation request, so I am prevented from creating Smart Collections / Smart Playlists.

The only viable workaround for me to successfully create them has been to run the Plex client from my NAS which doesn’t exhibit this problem.