Review for Auto Profile Picture by Dimitris
Rated 2 out of 5 stars
This functionality should be built-in in Thunderbird, but unfortunately it isn't. And unfortunately again, this seems to be the only extension that tried to tackle this, and as others have noted, it leaves a lot to be desired in terms of performance. In fact, the flickering and the general slow-down got so bad that I had to disable it. I hope the developer will fix those obvious issues.
To create your own collections, you must have a Mozilla Add-ons account.