Firefox problem

Hello, everyone.
I have the following problem: loading the page of Nextcloud>Files

  • with Firefox and Safari I don’t see any files.
  • with Chrome no problem.
    Do you have any ideas for solving the problem or troubleshooting?
    Note that: I have tried disabling some plugins but with no improvement and I have other installations of Nextcloud on other servers that work properly.
    Thank you very much

Some details:
Nextcloud version: 21.0.4
Operating system and version: Ubuntu 20.04.3 LTS
Apache version: Apache/2.4.41
PHP version: 7.4.3


Antivirus/Firewall/Add blocker plugin?

If that doesn’t help you, check the developer tools, if some resources are not loaded or blocked.