I try to solve this error since two days but with no success.
I use Discourse 2.0 (today) and used 1.9.x (yesterday).
I have a Ubuntu server with docker on it.
On the host I run nginx as reverse proxy with SSL offloading.
On the machine I host several docker images that run fine.
I installed Discource using “standalone.yml” with some modifications, e.g. port mapping from 80xx (host) to 80 (Discourse).
The Discourse URL from the Internet is something like this: https://discourse.example.com.
I try to embedd Discourse in a web site on a complete other domain, e.g. https://doc.test.dom
I added embedding settings to Discourse.
Failed to execute ‘postMessage’ on ‘DOMWindow’: The target origin provided (‘https ://discourse.example.com’) does not match the recipient window’s origin (‘https ://doc.test.com’)
I already tried to modify CORS settings in the Docker-Host-nginx.conf. No success.