Mozilla is going to stop supporting Mac OS X 10.4 aka “Tiger” with its Firefox development code. On the Mozilla Dev Planning Google Group, they addressed this.
“In September of 2009 we stopped supporting Mac OS X 10.4 (‘Tiger’) on mozilla-central but we left much of the code required to support that platform in the tree in case we wanted to reverse that decision,” says Mozilla’s Josh Aas. “We have come to a point where we need to make a final decision and either restore 10.4 support or remove this (large) amount of 10.4 specific code.”
“Mac OS X 10.4 was released in April of 2005 and a lot has changed since then,” he adds. “We would like to take advantage of more modern technologies on Mac OS X and 10.4 support has been a hindrance. Where we can work around supporting 10.4, doing so consumes valuable time and effort. Neither Chrome nor Safari has to deal with this.”
Mozilla will stop supporting Firefox 3.6 and Tiger sometime in 2011.