Review for SmartSave Thunderbird Extension by mkitwrk
Rated 5 out of 5 stars
SmartSave works great! It created all the folders and exported all the saved email I had (1997-2009) in one step. Out of 2GB (some 30K emails) only a few were skipped. I'll keep using it regularly so I never accumulate emails in such quantity again.
To create your own collections, you must have a Mozilla Add-ons account.