* [[If is Evil… when used in location context|https://www.nginx.com/resources/wiki/start/topics/depth/ifisevil/]] --- (always dangerous in locations, except when doing `return ...;` or `rewrite ... last;`)
* [[Install more_set_headers in nginx for Debian-based distro|https://serverfault.com/questions/954708/install-more-set-headers-in-nginx-1-15-8]] --- `apt install nginx-extras`, keeping in mind that it will rewrite the nginx core package, so any active nginx daemon will crash and need to be restarted.
** Apparently all extra modules get enabled by default after this installation, and some might crash on some systems: if so, delete their symlinks from `/etc/nginx/modules-enabled`.