Hello @torugo
Advanced customization allows hiding File and Collaborations tabs with following parameters:
However, as it is stated the While Label customization page:
The customization section allows you to customize the editor interface according to your needs, as well as change the presence or absence of additional buttons, links, change logos and other details of the editor’s owner.
On this page you will find the customization parameters available only for the extended white label license of ONLYOFFICE Docs Developer. To request a quote, please contact our sales team at sales@onlyoffice.com.