I have checked a lot of information from the Internet on this issue. I think these methods are too cumbersome and there are too many precautions.
It's really easy to find a method by yourself !!!!
As follows:
Step 1: configure the Thunderbird client in Windows or Ubuntu to send and receive emails normally. Note that you can place the configuration folder profile on both systems for normal access !!
Step 2: Modify the startup configuration file or directory of the two Thunderbird clients.
Unbuntu: Find the hidden directory in the home directory of the current OS user. thunderbird configuration folder, modify profiles. path = rruqn7mg In the INI file. default "configuration (which may not be yours ). Create a soft link pointing to the shared profile and change "rruqn7mg. Default" to this soft link.
In Windows: add the Thunderbird startup parameter "-profile = shared profile folder"
Step 3: OK :)