We already set the host header from our proxy.conf:

https://github.com/bitwarden/server/blob/master/util/Nginx/proxy.conf#L2

Should we just update that to include the port as well? Not sure how that might affect every endpoint though.

I was not sure about negative effects on other entpoints as well, therefore it was safer to just set the port for the admin entpoint. Maybe you can check if setting the port global does work fine ?

mmmh strangely enough I also use an alternate port in my config.ymlfile :
https_port: 9443
And I do not face this redirection issue 😕

I just tested this change and it breaks configs that are using 80/443. Trying to visit /admin is redirecting to https://domain.com:8443/admin/login?returnUrl=%2Fadmin

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