To install xul-ext-timeline just follow these instructions.
sudo apt-get install xul-ext-timeline
Which will install xul-ext-timeline and any other packages on which it depends.
|Maintainer||Debian Mozilla Extension Maintainers <email@example.com>|
|Description||adds a timeline above the Thunderbird status bar days) into the past and future. Events are shown as boxes spanning the relevant time period and tasks with due dates are shown as lines at the due date. All Day events are shown as lines along the bottom of the timeline in the relevant calendar colour.|