Security settings keep loading forever

Nextcloud version: 13.0.5
Operating system and version: CentOS 7.0 x64
Apache version: 2.4.6
PHP version: 7.1
Browser: Firefox 61.0.1 / Internet Explorer 11

The issue you are facing:
The security settings of any account take forever to load (it shows this hour glass image that keeps rotating). It just shows a field where I can enter an application name and a button to create a new app password. Other than that the page is empty. Note that I have at least 2 or 3 devices registered previously (a year ago) and those can access Nextcloud without a problem.
Additionally I have another issue that is probably related:

  • pressing the update button when there is a new version of NC available doesn’t do anything

Is this the first time you’ve seen this error?
Yes. I’ve been running Nextcloud for over a year now and never saw this issue (before 13.0.1). Synching between various devices works flawless. I have APCU installed as memory cache. Furthermore SELinux is enabled, but as far as I can see no entries are generated that are related to httpd. The logs in general do not show anything alarming to me. Nothing really changed other than that I updated Nextcloud to the latest. The previous version (13.0.1) also had this issue, that’s why I updated to 13.0.5. The update went flawless according to the report.

Steps to replicate it:

  1. Log in to any account using a webbrowser
  2. Go to the settings of your account
  3. Select security on the left

The output of your Nextcloud log in Admin > Logging:
I cannot access the log through the webbrowser, this page stays empty. However syslog doesn’t show anything alarming (as far as I can see).

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

<?php
$CONFIG = array (
  'instanceid' => '##########',
  'passwordsalt' => '###################',
  'secret' => '####################################',
  'trusted_domains' =>
  array (
    0 => '############',
    1 => '#########',
    2 => '##########',
  ),
  'memcache.local' => '\OC\Memcache\APCu',
  'datadirectory' => '/mnt/###########',
  'overwrite.cli.url' => '#################',
  'dbtype' => 'mysql',
  'version' => '13.0.5.2',
  'dbname' => '#####',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => '########',
  'dbpassword' => '###############',
  'logtimezone' => 'Europe/Amsterdam',
  'installed' => true,
  'log_type' => 'syslog',
  'logfile' => '/var/log/nextcloud.log',
  'loglevel' => 0,
  'log_rotate_size' => 10485760,
  'maintenance' => false,
  'theme' => '',
);

I managed to find the cause. It is because of a custom OTP app that was enabled. Once I disabled it (temporarily) I can access the settings again so I can change them.

.edit: strange that absolutely no (=zero) information about something going wrong, timing-out or whatever is logged. I even enabled debug logging as you can see in my config.php above.