[Solved] Wekan authentication reports timeout on LDAP connection

I have 2 UCS 4.4-1 Masters installed in different locations in different organizations that have the same behavior on a fresh Wekan install.

No login by users is possible. The user accounts are enabled for Wekan.
wekan-admin can login with password from /etc/wekan-admin.secret

See this extract from univention-app logs wekan (username, domainname and cert replaced):

[INFO] Init LDAP login "user123"
[WARN] Lookup for unset variable: INTERNAL_LOG_LEVEL 
[WARN] Lookup for unset variable: LDAP_USER_ATTRIBUTES 
[INFO] Init setup 
[INFO] Connecting "ldap://ucs.int.xxx.xxx:7389"
[DEBUG] connectionOptions{ url: 'ldap://ucs.int.xxx.xxx:7389',
  timeout: 10000,
  connectTimeout: 10000,
  idleTimeout: 10000,
  reconnect: true,
  log: 
   Logger {
     domain: null,
     _events: {},
     _eventsCount: 0,
     _maxListeners: undefined,
     _level: 30,
     streams: [ [Object] ],
     serializers: null,
     src: false,
     fields: 
      { name: 'ldapjs',
        component: 'client',
        hostname: '5f30e840c7a3',
        pid: 1 } } } 
[INFO] Starting TLS 
[DEBUG] tlsOptions {
  "rejectUnauthorized": false,
  "ca": [
    "-----BEGIN CERTIFICATE-----xxx-----END CERTIFICATE-----"
  ],
  "host": "ucs.int.xxx.xxx"
}
[ERROR] connection time out 10000
[ERROR] Error: Timeout 

What can I check to find out more about what’s causing it?
BR,
Jörn

After update to 4.4-2 and Wekan 3.42 the login is now working.

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