Canonical has just announced that Firefox 40.0 is now available in the official repositories for Ubuntu 15.04. Ubuntu 14.04 LTS, and Ubuntu 12.04 LTS.
The Ubuntu maintainers have been very quick to integrate Firefox 40.0 in the repositories, together with all the new features that have been implemented in the latest version of the browser from Mozilla. Usually, it takes a few days until maintainers get Firefox in the official repos, but it looks like they are doing a lot better now.
Submitted by: Silviu Stahie