My current set of add-ons, designed primarily for web development and power web surfing.
Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.
The Web Developer extension adds various web developer tools to the browser.
Use the Evernote Web Clipper to save things you see on the web into your Evernote account.
A customizable mouse gestures extension which enables to execute various commands and user scripts with six types of gestures.
Allows bidirectional access to Google Calendar
With Google™ Hangouts you can connect with friends and family while you browse internet. It brings conversations to life with photos, emoji, and even group video calls for free!
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 31+ only (see below for details).
Russian spellchecking dictionary
Australian English Dictionary for Mozilla applications.
British English Dictionary R1.19 for Firefox, Thunderbird and SeaMonkey by David Bartlett.
To enable, right-click in a multi-line text box, select "Languages", then "English / United Kingdom".