I was attempting to get acme / Let's Encrypt working on my WNDR3700v1 last month before I realized you cannot get certificates for naked IP's. About 2 days later I suddenly noticed that my LuCI web interface is no longer accessible. SSH works and the router is working normally but attempting to go to the router's page will redirect me to https and no login comes up.
This seems to be happening even though /etc/config/uhttpd has
option redirect_https '0'
and checking uci show uhttpd shows the same.
I just want to restart access to the LuCI web interface. Next steps?
No, this isn't helpful.
I don't want to wipe my configs, if I was I'd just factory reset it and LuCI would be fixed.
As I've said the router is accessible and working.
If you do not want SSL support for any of the packages that use the ustreamssl wrapper, mainly uhttpd and uclient-fetch (the wget replacement), you can just uninstall the libustream-openssl ot libustream-mbedtls (or whichever SSL lib you are using)
Removing that, making sure that /etc/config/uhttpd does not "force https, and restarting uhttpd should be ok.
And naturally you should sysupgrade to 18.06.9 or 19.07.5 (released yesterday).