Impersonate not working on Firefox

NextCloud version: 15.0.2
Apache or nginx version (eg, Apache 2.4.25) : Apache
PHP version:

Impersonate option is not working on firefox while its working fine on other browsers. I have cleared my cache and tried again but issue is still there.

The Impersonate app works fine with Firefox. You should try to use a a clean Firefox profile without any activated add-on and check if the problem still persists.