Review for Contacts Sidebar by Carbonize
Rated 5 out of 5 stars
@sr@ - Show me where it says Thunderbird 3. I think you need to slow down when reading to increase your comprehension. At a guess you are misreading "Thunderbirds 3-pane-window" which is is missing an apostrophe I admit but still makes sense. "Thunderbirds 3-pane-window" means the three areas or panes that Thunderbird uses to display folder list, email list and the email contents.
To create your own collections, you must have a Mozilla Add-ons account.