Give Sumatra a chance. At least under Windows. It requires a bit of love in terms of changing default color (e.g. single value in config file, from bright yellow to something toned down), but it super fast, lightweight and open wide range of formats (pdf, epub, mobi, djvu).

I (not OP) believe I have. It’s nice, but Zathura can use the same engine (MuPDF, which is responsible for the speed and format support, although Zathura also supports Poppler, which Sumatra has removed support for), and is beautifully vi-like. And what advantages does Sumatra have over pure MuPDF? DRM?

If I am not mistaken Sumatra is windows-only (zathura is cross platform) and enforces DRM (you can't copy from documents which disallow it). It is objectively an inferior option.

This, but at least in my Debian oldstable based distro, it requires Poppler, which the currently highest sibling of your post has pointed out has had vulnerabilities at least in the distant past (Edit: ~7+ years ago). (Edit the second: upstream also supports mupdf https://pwmt.org/projects/zathura/plugins/, but that’s had exploits as recently as 2017 on https://www.exploit-db.com/.)