I’m a bit new on this topic.
Do i need to change at my domain records ? Or are all subdomain forwared to the main IP and then seperated by the reverse proxy ?
You could try to add a trailing slash / in the destination URL or try without the /webmail path (just to see if it works in general)
Which webmail software is running at 192.168.1.2/webmail ? NS7 Roundcube?
Redirecting of the domain to the IP is working (needs a bit more testing)
But redirect to /webmail by a subdomain not.
I’ll try the extra slash / the next few days
I’m using Kopano on ClearOS as webmail.
A very good package which i like to keep for a bit longer.
I’m not very happy with Sogo or Webtop at the moment. A bit more limited then Kopano
Maybe you can configure Nextcloud to not use a path?
For example in NS7 Nextcloud could be configured to just use a virtual host name like nextcloud.domain.tld without the /nextcloud path, see Nextcloud — NethServer 7 Final