"The page isn’t redirecting properly" after fresh install & first login

Hi everyone, after a fresh install of the Pi and Nextcloud, right after creating the admin user and entering the DB details, I get this Firefox error upon navigating to <raspi_ip>/nextcloud/:

The page isn’t redirecting properly
Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
This problem can sometimes be caused by disabling or refusing to accept cookies.

If I block cookies, the login page comes up, but if I allow cookies again and log in, the error reappears.

Config

My /var/www/html/nextcloud/.htaccess is unchanged, I created the /etc/apache2/sites-available/nextcloud.conf as described in the installation guide:

Alias /nextcloud "/var/www/html/nextcloud/"

<Directory /var/www/html/nextcloud/>
  Require all granted
  AllowOverride All
  Options FollowSymLinks MultiViews

  <IfModule mod_dav.c>
    Dav off
  </IfModule>
</Directory>

The /var/www/html/nextcloud/config/config.php:

<?php
$CONFIG = array (
  'instanceid' => 'ocfzxx9gus6k',
  'passwordsalt' => 'c91+l/RRvDFhttgnLZkiMr30uNQW2w',
  'secret' => 'BgX9hAoiz+FBserSRl0l6wZzwVw0F1Gpkyk7f+WkscWUGKse',
  'trusted_domains' => 
  array (
    0 => '<raspi_ip>',
  ),
  'overwrite.cli.url' => 'http://<raspi_ip>/nextcloud',
  'datadirectory' => '/var/www/html/nextcloud/data',
  'dbtype' => 'mysql',
  'version' => '25.0.1.1',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'nextcloud',
  'dbpassword' => '<pw>',
  'installed' => true,
  'maintenance' => false,
);

PHP version 8.0.25


It seems to be a similar problem to this problem (unsolved) but with apache2 instead of nginx and without any SSL steps taken yet.

Does anyone have an idea on what could cause this problem?