How to edit a link in a post?
 

I keep running into this - I've posted a link, and then I need to edit some portion of it, but I can't. For example, I post egxample. Then I want to edit the link, either because of the spelling error or for some other reason. But when I open the edit screen, I can't get at the underlying bones of the link.

How can I edit a link once it's been posted?