The community member has a page called /extra and wants to redirect it to https://extra.mywebsite.com, assuming they have added their custom domain via a flattened CNAME. The comments suggest that the community member initially encountered an error message stating "must start with a /", which discouraged them, but they later realized they just needed to write the full URL, which worked. Another community member advised adding the protocol (https://) to the URL where the redirection is happening, since it's an external site. A link to a related GitHub pull request was also provided.
I have a page called /extra and I would like to redirect that to https://extra.mywebsite.com assuming I add my custom domain via usual flattened CNAME.
You're right it is possible! When I tried, I got this message and that discouraged myself. I just needed to continue writing the full URL and it is ok.
