Two weeks ago we got an unexpected Firefox 184.108.40.206 release in order to fix a critical bug. In another three weeks or so, September 7th to be exact, we should be receiving Firefox 220.127.116.11! Mozilla just keeps on pumping out these updates.
Their primary goal for this build is to address some possible security issues and any regressions, like always :) . All of the nominations for bug fixes had to be in 2 days ago and the first candidate is scheduled to be available on August 28.
For more details you can checkout the Firefox 18.104.22.168 Planing Page.