This trouble occurred with the installation of Mozilla Thunderbird on my Windows PC 10. I noticed that the 1TB SSD was almost full. With the help of TreeSize, tip from Wander, found out that the main culprit was the Thunderbird, occupying 469,2 GB.
In the settings of Synchronization and Storage, unchecked the redundant folders on the Gmail, as “All emails”, “With star”, and “Important”, and also that of “Spam”, that there’s rarely anything I can’t dismiss just by the subject line. I also configured synchronization to keep only messages received in the last year locally.
But, the Mozilla Thunderbird continued to occupy a very large space on the SSD, even with frequently asked questions about compressing folders to save space, that apparently didn't make any difference.
A solution came with the installation of XPunge extension. This extension adds options in the wrench menu to clean the trash and compact folders. This option did quickly eliminate all the fat from the Thunderbird. Now Thunderbird is occupying 69,3 GB. It's not exactly little, but it is reasonable for the amount of emails I have.