Development of 64-bit Firefox for Windows is dead. As hard to believe in this 64-bit world, it seems that 32-bit apps still rule. On Friday, Mozilla engineering manager Benjamin Smedberg posted a thread over on the Google Groups mozilla.dev.planning forum called “Turning off win64 builds”, due to various problems with them. After a somewhat lively discussion, he decided to pull all 64-bit development on Wednesday, meaning that a 64-bit version of Firefox will unfortunately never be relesed.
Thank you to everyone who participated in this thread. Given the existing information, I have decided to proceed with disabling windows 64-bit nightly and hourly builds. Please let us consider this discussion closed unless there is critical new information which needs to be presented.