Ublock add-on for Firefox is now available on Mozilla add-ons site for download, so you no longer need to visit the developer site or the add-on releases page on Github to install it. Ublock –now supports Firefox 29.0 -39.0– once installed in Firefox will be automatically updated whenever developer publishes a new version to AMO.
Ublock (Beta) is now available for Firefox (on github)
Download Ublock for Firefox from AMO
Ublock is more than an adblocker, it uses the same filter lists which the most popular Adblock Plus uses and offers the same protection. This add-on developer has compared Ublock and ABP efficiencies, check this page for more details.
UPDATE: Here is the link for Ublock Origin (who created the ublock first)