Rated 5 out of 5 stars

Great addon. I use Thunderbird Conversations addon, so is it possible to make it compatible with it ?

סקירה זו מתייחסת לגרסה קודמת של התוספת (1.3.0.4). 

I'm sorry but it is impossible. The amount of work to make them compatible is comparable to the amount of work to merge these addons into one single addon. Here is more detailed explanation: http://mnpforum.alehro00.com/Message-Notes-Plus-for-Thunderbird-1-2-2-9-td4337293.html