Anna's Task Tracker от Kota

A simple no frills sidebar todo list. Enter in new items and check them off as you're working with a progress bar to keep you motivated. Clicking minus removes an item, clicking the item itself marks it as done.

Opens with Control + Alt + A if nothing else is using that hotkey. Otherwise you can open your sidebar by pressing Alt and then clicking View > Sidebar > Anna's Task Tracker.

If you use firefox sync you'll be able to use your task list on multiple computers.