I have done a Google search and asked ChatGPT how to do this and none of the solutions I have tried have worked. I have tried the ImportExportTools NG. I know how to browse to where the local folders for Apple Mail are stored in the Library folder on my Mac mini. I am running the current version of Mac OS Sonoma. I just don't know what to do. I want to move to Thunderbird email but I need to be able to migrate the Local folder with its' sub-folders in Thunderbird. Again I have spent many hours trying to accomplish this and am more technically more than the average user. One more thing. I currently do most of my work on my Mac but have an SSD attached to it where I run Linux Mint. The second issue is if I am able to import these Local folders into Thunderbird or either Linux or Mac OS will they sink to the other OS. What I have done with some other programs is that I have a partition on the SSD in my Mac mini that is formatted as exFAT. One example is the program Moneydance. Its' data is stored on this exFAT partition so that whether I am booted into Mac OS or Linux my data is current. I feel there has to be another Mac OS Sonoma user who has found a way to accomplish this.