PDF readers
- zathura/mupdf/katarakt/…: No ability to use the document Table of Content, fine for things with ~20 pages, utterly unusable for big reference documents
- evince (gnome): Horrible UX, like zoom resetting to a stupid value if you use the Tables of Contents in the sidebar, of course it's gnome so there's no preferences
- Okular (KDE): *pulls a whole whole bunch of stuff that I do no want on my machines*

Bloody paper is better at this point.