Steps to reproduce the issue

1. install new fresh jos5.0.1 (seen since 5.0.0)
2. create your own custom media dir inside webroot, e. g. "mediatest" and the subdir "img" for images
3. go to system => global configuration => media
4. change "path to files folder" to "mediatest" an "path to images folder" to mediatest/img"
5. save and exit
6. go to content => media

Expected result

the content of the new custom media dir is shown (empty in the upper case)

Actual result

the content of the default media dir "/images" is still shown

System information (as much as possible)

jos5.0.1 (clean and new installed from zip https://downloads.joomla.org/)
php8.1.26 fpm-fcgi
kernel 5.10.0-25-amd64
10.8.8-MariaDB

Additional comments

clear cache and log out and in again did not fix it