diff --git a/docs/third_party-roundcube.md b/docs/third_party-roundcube.md
index dd2a99b18..d079db753 100644
--- a/docs/third_party-roundcube.md
+++ b/docs/third_party-roundcube.md
@@ -152,3 +152,62 @@ $MAILCOW_APPS = array(
 );
 ...
 ````
+
+### Let admins log into Roundcube without password
+
+First, install plugin [dovecot_impersonate](https://github.com/corbosman/dovecot_impersonate/) and add Roundcube as an app (see above).
+
+Edit `mailcow.conf` and add the following:
+
+```
+# Allow admins to log into Roundcube as email user (without any password)
+# Roundcube with plugin dovecot_impersonate must be installed first
+
+ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE=y
+```
+
+Edit `docker-compose.override.yml` and crate/extend the section for `php-fpm-mailcow`:
+
+```yml
+version: '2.1'
+services:
+  postfix-mailcow:
+    environment:
+      - ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE=${ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE:-n}
+```
+
+
+Edit `data/web/js/site/mailbox.js` and the following code after [`if (ALLOW_ADMIN_EMAIL_LOGIN) { ... }`](https://github.com/mailcow/mailcow-dockerized/pull/3849/commits/1c873a83b5e6b1714512b2dc79ff81b26af3ef79#diff-aac7eb6ff52acc8698ff9bcc71c313cbc5bbbe501c3eb1b8bc658ef97fb9d4c1)
+
+```php
+if (ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE) {
+	item.action += '<a href="/rc-auth.php?login=' + encodeURIComponent(item.username) + '" class="login_as btn btn-xs btn-primary" target="_blank"><span class="glyphicon glyphicon-envelope"></span> Roundcube</a>';
+}
+```
+
+Edit `data/web/mailbox.php` and add this code to the bottom of the [javascript section](https://github.com/mailcow/mailcow-dockerized/pull/3849/commits/1c873a83b5e6b1714512b2dc79ff81b26af3ef79#diff-312fb7af69e284eca2fd573cdf2e4c3d04b6cd93fc5eb0e4dcdc6c199afd0aba):
+
+```php
+<script type='text/javascript'>
+<?php
+// ...
+$ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE = (preg_match(
+  "/^(yes|y)+$/i",
+  $_ENV["ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE"]
+)) ? "true" : "false";
+echo "var ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE = " . $ALLOW_ADMIN_EMAIL_LOGIN_ROUNDCUBE . ";\n";
+?>
+</script>
+```
+
+Copy the contents of the following files from this [Snippet](https://gitlab.com/-/snippets/2038244):
+
+* `data/web/inc/lib/RoundcubeAutoLogin.php`
+* `data/web/rc-auth.php`
+
+Finally, restart mailcow
+
+```
+docker-compose down
+docker-compose up -d
+```