For your knowledge:
Running PHP version: 8.1.12 on Debian testing
Just upgraded to 1.6RC and updated Libratus to version from 24.11.2022.
All caches cleared/purged and still no change.
{138394:Sun, 27 Nov 2022 10:40:26 GMT}
WARNING: Undefined array key 0 in /var/www/html/zp/themes/libratus/inc-header.php on line 28
include called from include (album.php [1])
from include (index.php [128])
from index.php [79]
{138394:Sun, 27 Nov 2022 10:40:26 GMT}
ERROR: Call to a member function getCustomImage() on null in /var/www/html/zp/themes/libratus/inc-header.php on line 29
Please open tickets on the theme's repository. We will not be able to look into updating these "half 3rd party themes" before 1.6. itself is released. https://github.com/zenphoto/libratus