CMS Made Simple Forums

I have guessed the answer to this now and have it working, but wanted to ask on behalf of other new users:
Likely dumb question new-user question, but I can't find the answer in a search here or the docs.
When I create a link on a page, in a news article, etc, to an external website e.g. xyz.abc.com/page.htm, from cms.mysite.org, the CMS makes the link point to cms.mysite.org/xyz.abc.com, and to get it to point just to the desired target URL, the only thing I can find is that you have to put in a second "/" after the http in the link using the html view.
I can see why there might be a need to differentiate between onsite and offsite links, but is the help on this hidden or hard to find, or am I just using the wrong search string?
It would be really good if there was a hint on the link creation dialog, or a check box or similar to differentiate.
Thanks, Mort

It does give a warning if you start with 'www' like www.cmsmadesimple.org, but it doesn't if you are going to a subdomain like dev.cmsmadesimple.org.

It is asking for a link, properly formed links begin with http://,https://, or // unless they are relative.