Problems with the Editor and not-Markdown Files

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1

Nextcloud version: 18.0.2
Operating system and version: Debian 10.3
Apache or nginx version: Apache 2.4.38
PHP version: 7.3.15

The issue you are facing:
If I open any Text-File in the interface, that is not a Markdown-File, the Editor loads infinitely. A look into the Network-Traffic shows that the content of the file is sent to the Frontend.
*.txt-Files sometimes work but Files like *.java or *.yaml won’t.

Is this the first time you’ve seen this error?: Yes

Steps to replicate it:

  1. Upload any non Markdown-File
  2. Open the Network-Tab of the Developer tools in your Browser
  3. Try to open the file within the Web-Interface
  4. Wait

The output of your Nextcloud log in Admin > Logging: Nothing

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

<?php
$CONFIG = array (
  'instanceid' => '[REMOVED]',
  'passwordsalt' => '[REMOVED]',
  'secret' => '[REMOVED]',
  'trusted_domains' => 
  array (
    0 => 'cloud.domain.tld',
  ),
  'datadirectory' => '/var/www/domain/cloud/data',
  'overwrite.cli.url' => 'https://cloud.domain.tld',
  'dbtype' => 'mysql',
  'version' => '18.0.2.2',
  'dbname' => '[REMOVED]',
  'dbhost' => '[REMOVED]',
  'dbport' => '',
  'dbtableprefix' => '[REMOVED]',
  'mysql.utf8mb4' => true,
  'dbuser' => '[REMOVED]',
  'dbpassword' => '[REMOVED]',
  'installed' => true,
  'htaccess.RewriteBase' => '/',
  'mail_smtpmode' => 'smtp',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_from_address' => 'cloud',
  'mail_domain' => 'domain.tld',
  'mail_smtpauth' => 1,
  'mail_smtphost' => '[REMOVED]',
  'mail_smtpport' => '[REMOVED]',
  'mail_smtpname' => '[REMOVED]',
  'mail_smtppassword' => '[REMOVED]',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'maintenance' => false,
  'theme' => '',
  'loglevel' => 2,
  'mail_sendmailmode' => 'smtp',
  'mail_smtpsecure' => 'ssl',
  'updater.release.channel' => 'stable',
  'default_language' => 'de',
  'default_locale' => 'de',
  'allow_user_to_change_display_name' => false,
);

The output of your Apache/nginx/system log in /var/log/access.log (error.log is empty):

93.213.237.236 - - [17/Mar/2020:12:49:14 +0100] "PROPFIND /remote.php/dav/files/[REMOVED]/[REMOVED].java HTTP/1.1" 207 2764 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:74.0) Gecko/20100101 Firefox/74.0"
93.213.237.236 - - [17/Mar/2020:12:49:15 +0100] "GET /apps/text/session/create?fileId=8159&filePath=[REMOVED].java&guestName=null&forceRecreate=false HTTP/1.1" 200 1488 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:74.0) Gecko/20100101 Firefox/74.0"
93.213.237.236 - - [17/Mar/2020:12:49:15 +0100] "GET /apps/text/session/fetch?documentId=8159&sessionId=74&sessionToken=[REMOVED] HTTP/1.1" 200 1709 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:74.0) Gecko/20100101 Firefox/74.0"
2

Created an issue here: