So that I am understanding this behaviour correctly, if I wanted to host my own website (using the router as reverse proxy), then I am not able to setup NGINX to listen on both port 80 and 443 as the firmware is refusing to release port 80? It is usually pretty standard to put a redirect in NGINX to redirect incoming connections on port 80 to 443. Or are we taking about port 80 being tied down on LAN (br0) while the WAN port is still ok to use port 80 and 443?
Both
@thatdoodle and you need to be more precise about how you've configured NGINX, and where it's running. Don't assume we should just know. It could be on the router, or internally on the LAN. It could be a proxy, or reverse proxy. It could be bound to the WAN, the LAN, or BOTH. Without such details, it's difficult to provide accurate answers or address your concerns.
My assumption w/
@thatdoodle was that he was running NGINX on the router and wanted it bound to the LAN (port 80), which is in conflict w/ the GUI. So he changed the GUI's LAN port to something else (e.g., 8080). And while that solved the problem, it came at the unexpected expense of having the GUI now running on the new port w/ HTTP, when he had specifically requested only HTTPS for the LAN authentication!
That's why I consider it a bug. Had he never needed port 80 for NGINX and simply wanted to limit LAN authentication to HTTPS, the router would NOT have bound the GUI to HTTP/80.
Now when it comes to the WAN side, the GUI is never bound to the WAN. If you enable remote access, then HTTPS is required and a port is opened (8443 by default, although you can change it), where the inbound traffic is redirected (via DNAT) to the GUI on the LAN side (port 80 by default, for http, or 8443, for https, unless you changed these for some reason).
In short, unless you're replicating
@thatdoodle's configuration, there shouldn't be any issues w/ port forwarding or opening ports 80/443 on the WAN. At least NOT as far as the GUI is concerned (I can't speak to other services that might also find those same ports appealing, e.g., AiCloud).