After a recent upgrade of Thunderbird I started getting pop-ups about compacting folders. This was not unusual, but it now pops up every couple of hours and states it will recover 6.4 GB of disk space. No matter how many times I do this (click on compact now). It keeps coming up with the same size disk savings. This has been going on for over a month. Even the many times it has been rebooted this behavior does not change. Is there something that is being detected that is not getting compacted? Is it usual for this to happen so frequently? How do I handle this so it does not keep doing the same thing? It's driving me nuts.