"Additional Settings" not available in GUI / can' t configure "File handling" max upload size

Nextcloud version:, official docker image with automatic update
Operating system and version: Debian 10 / Docker 19.03.2 (API: 1.40)
Apache or nginx version: Apache
PHP version: 7.3.9

The issue you are facing:
I follow the instructions to increase the maximum file upload size from 2MB to 3.9GB.

In the GUI the new limit of 3.9GB is confirmed to me as admin under “Informations” > PHP - so the modification of php.ini seems to have worked.
According to the instructions I finally have to configure the “File handling” in the GUI as admin. This input field should be under “Additional Settings”, correct?

Unfortunately, exactly this area is not available in the navigation bar.
Via the direct URL /settings/admin/additional only an empty page is displayed.

Note: Already before the modification the “Additional Settings” were not accessible.

Is this the first time you’ve seen this error?

Steps to replicate it:
Follow these instructions.

The output of your Nextcloud log in Admin > Logging:
OnlyOffice has been deactivated and removed and is no longer needed.