Firefox will automatically remove the Lab Kit add-on early next week
to restore Firefox's add-on update functionality and avoid potential
stability and security problems.
The add-ons currently bundled in Lab Kit [1] are still available
individually. They're all Mozilla Labs add-ons [2].
Ed
[1] http://mozillalabs.com/your-lab-kit-contents/
[2] https://addons.mozilla.org/en-US/firefox/user/5133025/