accounts/account page unresponsive after adding the 2FA addon using nginx without docker

[sylvanr]

Hey!

Would like to flash back to an issue that was raised on the main cockpit repo: Cockpit Issue - 2FA authentication question

Context:
Using ubuntu 20.04
I use a direct installation (so no docker) - cockpit-next and cockpit-master result in the same situation.
Using nginx as the webserver.
Simply adding the 2FA folder to the cockpit/addons folder by following the instructions here

Result:
500 code in the console, no errors in the error log, only a single row with response 500 in. the access log.
And the page looks like
this, same picture as the former issue

Curious to hear if you have any tips on debugging this issue!
Would be great to have resolved.