After the latest changes, a lot of things broke on XKit as you know.

After a couple of hours of reverse-engineering and guessing and losing my hair, I’ve fixed the following:

XInbox

• No longer breaks the toolbar on the New Post / Reblog Post “windows”
• Tagging people are disabled for now since I don’t know how to make it work with the new system

One-Click Reply

• Now can tag users as before.
• Replying from dashboard works again.
  

Go-To-Dash

• Fixed a bug that would cause the “view” button to appear even if you are not following that person.
  

And finally:
One-Click Postage

• Yep, it works as usual now.

Sorry about the delay, they’ve changed the whole back-end so it took hours to figure out how to re-write those extensions (and re-writing them.)

UPDATE:

Also, please check this and this post.