Thunderbird needs Conversation mode

Coming from GMail back to Thunderbird on my laptop I'm experiencing all the issues that GMail neatly fixed.

Displaying email threads in "Conversation mode", hiding top posts (see email 101). Reply to an email you've sent and the reply only goes to yourself.. not the same people in the first email.! -- it's a long list. Not even sure if Thunderbird is maintained any more, it hasn't had any new features since it was Mozilla messenger back in 2000 as far as I can see. Addons are good though ;)