Hyperlink validation is not clear

[SteveMarvin]

Most users will be used to the idea that they can enter "www.microsoft.com" as a valid URL. If that is entered as an external link in DM2, it will say "Please enter a valid URL". The "http://" prefix is required. It might be good to add that prefix on by default if it or "https://" is not present already.

Alternatively, notify the user to add the Protocol Identifier (with an example).

[MartinFoys]

External link making tool is extremely limited - cannot edit or delete — also, currently cannot test link made when doc is checked out.