Solid servers can be a) a Pod provider b) an Identity Provider or c) Both. https://solidcommunity.net is both as is https://inrupt.net. So when that dropdown asks for an Identity provider, it is not asking for your WebID, it is asking the origin - the place you got your WebID from. If your WebID was issued by https://pod.derOpa.io, then you should put that in, not your full WebID, if you get the same response, that means that the server’s Identity Provider is not spec compliant.
wow thanks for the info. totally a tourist here. link to my home-server is with a zero https://pod.der0pa.io … currently returning the pwdirectory… running a very simple reverse-proxy with nginx. thanks again.
back again this year! 
running solidos on a M1 mac. no -problems on localhost:8443. all seems to work
got a static ip 76.161.87.249 and have port-forwarded. 80 443
(base) douglassmith@Douglass-MacBook-Pro Sites % nc -z -v 76.161.87.249 30-9000
static-76-161-87-249.dsl.cavtel.net [76.161.87.249] 80 (http) open
static-76-161-87-249.dsl.cavtel.net [76.161.87.249] 443 (https) open
static-76-161-87-249.dsl.cavtel.net [76.161.87.249] 7547 (cwmp) open
firewall on mac is turned off
i’ve tweaked all settings in modem/router …
ip always resolves to modem login pod.der0pa.io
any idea what i’m doing wrong?
started solidos by:
(base) douglassmith@Douglass-MacBook-Pro solidos % npm start watch