Access to Google contacts and synchronize them with Thunderbird address books.
This addon provides a conversation view for Thunderbird, grouping messages together and allowing you to reply "inline" thus providing a more efficient workflow.
The latest version is compatible with Thunderbird 38+ only (see below for details).
It adds some options to launch easily other profiles and the Profile Manager.
QuietUrl automatically converts mistyped or obfuscated URLs to valid ones, can obfuscate URLs on form submission for privacy and it also creates clickable links from text URLs, which works with incomplete URLs as well, like those in YouTube comments.