inspiration:
perishablepress.com/better-default-directory-views-with-htaccess/

apache-conf:

IndexOptions SuppressHTMLPreamble FancyIndexing
HeaderName /dirlist-header.html

shell vscode remote:

code /etc/apache2/sites-enabled/000-default-le-ssl.conf
apachectl restart

php (disabled):
[php $dir = explode('?', $_SERVER['REQUEST_URI']) [0]; ]
[= $dir ]
/dirlist-header.html contents: [[
]]