What is "thundermail" and why is it in my way?

"Thundermail" is Thunderbird's upcoming commercial email hosting service. Here's a description:

https://blog.thunderbird.net/2025/04/thundermail-and-thunderbird-pro-services/

It's not available yet, but you can sign up for the waiting list here if you're interested.

https://tb.pro/en-US/

It's said that the service will be tightly integrated with Thunderbird (the familiar email app,) but of course, Thunderbird will always be able to be used with other email services as it is now.

Thanks for the update. I will likely subscribe to Thundermail; the $72 annual price works for me.

I do have a problem with Thunderbird 153.0.3. It does not appear to use data files from older versions of Thunderbird, which means all email accounts have to be entered again.

It also seems that there is no automatic conversion of the older data files to the new 153.0.3 format.

Please advise on how I can migrate my existing Thunderbird data and accounts to version 153.0.3.

Thanks.