What happened to the web site?
At present, it is impossible to reach the web site the English Wikipedia entry refers to
https://pwmt.org/projects/zathura/
This is the same observation with what could be the parental address
There are snapshots by archive.org (example) to access the documentation and previous releases (e.g., version 0.4.8 by 2021/07/14; entry). Package managers however may offer the current release 0.4.9 (example Debian).