Password app does not work behind reverse proxy

Nextcloud version (eg, 12.0.2): 17.0.1.1
Operating system and version (eg, Ubuntu 17.04): docker, host archlinux
Apache or nginx version (eg, Apache 2.4.25): docker
PHP version (eg, 7.1): docker

The issue you are facing:
When i
Steps to replicate it:

  1. use docker image,
  2. create reverse transperant proxy using caddy,
  3. see it grip about no ssl

I dont know exactly, but i have nextcloud docker image on 192.168.0.115:80, and the main server which is my URL is 192.168.0.101

It appears to be griping because the connection between nextcloud and the docker container is http, while the clearnet address is TLS/SSL

The output of your Nextcloud log in Admin > Logging:

[passwords] Error: OCA\Passwords\Exception\ApiException: HTTPS required at <<closure>>

0. /var/www/html/lib/private/AppFramework/Middleware/MiddlewareDispatcher.php line 95
   OCA\Passwords\Middleware\ApiSecurityMiddleware->beforeController(OCA\Passwords\Co ... {}, "update")
1. /var/www/html/lib/private/AppFramework/Http/Dispatcher.php line 97
   OC\AppFramework\Middleware\MiddlewareDispatcher->beforeController(OCA\Passwords\Co ... {}, "update")
2. /var/www/html/lib/private/AppFramework/App.php line 126
   OC\AppFramework\Http\Dispatcher->dispatch(OCA\Passwords\Co ... {}, "update")
3. /var/www/html/lib/private/AppFramework/Routing/RouteActionHandler.php line 47
   OC\AppFramework\App::main("AdminSettingsController", "update", OC\AppFramework\ ... {}, {id: "service.fa ... "})
4. <<closure>>
   OC\AppFramework\Routing\RouteActionHandler->__invoke({id: "service.fa ... "})
5. /var/www/html/lib/private/Route/Router.php line 297
   undefinedundefinedcall_user_func(OC\AppFramework\ ... {}, {id: "service.fa ... "})
6. /var/www/html/lib/base.php line 1000
   OC\Route\Router->match("/apps/passwords ... n")
7. /var/www/html/index.php line 42
   OC::handleRequest()

PUT /apps/passwords/admin/settings/service.favicon
from 162.158.107.148 by merith.tk at 2019-12-09T18:45:07+00:100

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

<?php
$CONFIG = array (
  'htaccess.RewriteBase' => '/',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'apps_paths' => 
  array (
    0 => 
    array (
      'path' => '/var/www/html/apps',
      'url' => '/apps',
      'writable' => false,
    ),
    1 => 
    array (
      'path' => '/var/www/html/custom_apps',
      'url' => '/custom_apps',
      'writable' => true,
    ),
  ),
  'instanceid' => 'ochnegiyljer',
  'passwordsalt' => 'nsMS3t+OljgznSEKx9R74hmseubZ/p',
  'secret' => '6xdhOrBPn6vO+uyvh7raH66BGOfrCXQdD/dz868CA3+ExyHW',
  'trusted_domains' => 
  array (
    0 => 'next.merith.tk',
  ),
  'datadirectory' => '/var/www/html/data',
  'dbtype' => 'mysql',
  'version' => '17.0.1.1',
  'overwrite.cli.url' => 'http://next.merith.tk',
  'dbname' => 'nextcloud',
  'dbhost' => '192.168.0.115:3306',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'nextcloud',
  'dbpassword' => '',
  'installed' => true,
  'maintenance' => false,
  'theme' => 'nextcloud-breeze-dark',
  'loglevel' => 2,
);