This repository contains a PowerShell script which creates a backup of the %APPDATA%/Thunderbird folder.
To use this script, you must be running PowerShell on a 64-bit version of windows and you must have 7-zip installed.
Download the PowerShell script and then run it either by double-clicking the file or by right-clicking and selecting "Run with PowerShell".
It may take some time to run.
When the script completes, you will find Thunderbird.7z on your Desktop.