Custom sync interval for Lightning Calendar Requires Restart

Allows custom synchronization intervals for remote calendars imported by Lightning Calendar (no fiddling in about:config necessary)

iCanban - Kanban with ICAL

Multimonth view

Multimonth View allows users to display multiple months in a single calendar view,

All Events

Show past, future or all events

Date Time Formatter

Shows relative date-time in the column.
Note: you need to click "Select columns to display" and then -> "Relative Date/Time"

CalendarSearchExport

Exports the results of a search in calendars

ElsHelp

Extension for ElSchool diary

Iranian Date For Thunderbird Requires Restart

Adds a new Iranian(Persian/Jalali) date column to Thunderbird.

marked-lightning

Extension for Lightning: Allows the use of Markdown in Task descriptions and renders them as HTML in the TaskView.

M-Hub Lite

Add Microsoft Office 365 Tabs to Thunderbird! Services supported by M-Hub Lite: Calendar, People, OneDrive, Word, Excel, PowerPoint, & Bing. Need business or enterprise support? Get M-Hub Pro: https://www.schiffner.com/software/m-hub-pro

Mahoor-Iranian-Date

This add-on adds a new column called "تاریخ" ("Date (Persian)" since V1.1.3) in message list containing Iranian Date.

It is reimplementation of Iranian date for Thunderbird 78+ and 115+. The source is based on Full address column by Łukasz Kosson.

Enhanced Date Formatter Requires Restart

Configure the 'Date' and 'Received' columns and displayed date in the message pane using custom formats. You can even use different date formats for emails with today's date, yesterday's date, dates in the last week, or dates older than a week.

Show Outlook Appointments (vcal / ics) Requires Restart

An extension to show embedded Outlook calendar (vcal / ics) parts.

Thunderbird doesn't show calendar parts from Outlook appointment emails. This addon adds a button to download the embedded appointment as ICS to import it into another calendar.

Events spanning multiple days Requires Restart

Displays multiple day events as a "spanning" event, without borders of the day-elements inside the month- and multiweek-view.

Jalali Date Format Requires Restart

Convert Date/Received column to Jalali (Persian Date).

* Adds a column in the mail view for displaying Iranian dates for each email.
* Supports both English and Persian Iranian Date.

more info contact N3tD3vil@Yahoo.com

AdvancedTasks Requires Restart

Thunderbirds Lightning Extension: Allows the use of Markdown in Task descriptions and renders them as HTML in the TaskView.

lightningWeather Requires Restart

LightningWeather shows the weather forecast in the background of the calendar so you can easily coordinate your activities with the weather.

ConferenceCall.co.uk templates

This plugin adds our savvy email templates to your Thunderbird toolbar.

Telefonkonferenz.de-Vorlagen

Durch das Plug-in werden unsere praktischen E-Mail-Vorlagen Ihrer Thunderbird-Symbolleiste hinzugefügt

ConferenceCall.nl templates

Voegt de handige e-mail templates toe aan de knoppenbalk van Thunderbird om deelnemers aan uw conference call uit te nodigen.