Timeline is a free and open source timeline application for Linux and Windows.Using this you can display the event and navigate events on a timeline.It is released under GNU General Public License version 3 license.you can scroll and zoom your events with mouse wheel .Some other features are navigate to a specific date in your timeline.you can also search and organize your events.You can set the events in hierarchical categories order and export your timeline to image.It also comes with duplicate, move and resize events features. .
Install Timeline on Ubuntu:
You can install Timeline via the snap package manager on Ubuntu.open your terminal app (ctrl + alt + t) and run this Timeline snap installation command.
sudo snap install timeline
Then enter your Ubuntu user password to confirm the installation if needed.It will install the latest version of Timeline application on Ubuntu.click the show applications in the Ubuntu Gnome dock and type Timeline in the search box and click Timeline to open it.
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In terminal type below command and hit enter start it, if you like the command line mode.