Hey @lxof 
To increase the number of connections in ONLYOFFICE, you’ll need a license that covers the required number of connections. For more detailed information and assistance in choosing the right license, feel free to contact our sales department.
To activate your license, you will need to use either the Developer Edition build (DE) or the Enterprise Edition build (EE) of the document server.
ONLYOFFICE Docs Community is available under an open-source license - AGPL v3.
For more information, visit: ONLYOFFICE License FAQ and Compare ONLYOFFICE Docs editions.
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Remove connection limits