How do I edit the tags with this great new interface?

Sure the new "improvements" look good, but I feel like we've lost some
usability.  It used to be a cinch to edit the tags on a bookmark I've
got tagged.  I can't find an edit button.

How do I edit the tags on a bookmark that's already in my list.
Posting it as new is not convenient.

And cheese! I keep getting blocked by pressing the buttons on the
webpages!