[yetanother12345]

>"If I got the 'polished' version as part of the normal update cycle I'd be upset"

Thanks! Glad you mentioned it! On Linux the Thunderbird update is just one among many other updates in an update batch, so usually it will just be installed with the rest of the updatable items. I will have to pay attention now, so I don't install this unwittingly.

> "The point of email is to communicate information"

Deserves repetition.

> have to interact with the UI

This interaction is a cost, and you pay. I like mine cheap.

[velosol]

For Windows they're not pushing current 102 users to the new design yet. This matches some of the previous rollouts where the auto-upgrade branch is treated a bit more like 'stable' or 'ESR' might be in Linux and Firefox ESR.