Firefox still doesn't run each tab in a seperate process, but they put a stop to the various memory bloat and tab deadlocks quite a while ago. On my mac, the same instance of firefox stays running until I reboot (which is weeks or months apart), and it seems to always release the memory that a closed tab was using.
I think one of the early 20s (24 maybe?) was all about stability stuff like this.
Biting the hand that feeds IT
