Hi, details of environment:

Piwigo 15.3.0
Installed 15 January 2025
OS: Linux
PHP: 8.2.26 (-) [2025-01-15 01:11:05]
MySQL: 10.11.6-MariaDB-0+deb12u1 [2025-01-15 01:11:05]
Graphics Library: External ImageMagick 6.9.11-60

Fresh piwigo installation. Couldn't find the "community" plugin on the available list at administration pages, downloaded and installed manually.

When uploading as an unregistered user, the upload fails, and on the logs, the message:

Got error 'PHP message: PHP Warning:  Undefined array key "who_options_selected" in... file.admin_permissions.tpl.php on line 463
Got error 'PHP message: PHP Warning:  Undefined array key "quota_details" in... file.add_photos.tpl.php on line 692

Uploading as a registered user works fine. Greetings!