Timeline tab is located under the Computer Activities reports on the left side menu:

Overview

The timeline report shows a chronological view of registered computer activities. Here you can use the date range filter and compare when and what activities were tracked during your workday.

 If you hover your mouse over a specific segment, you'll get information about the activity name and its timeframe.

You can export the Timeline report to an Excel file. 

The downloaded report will contain the name of a user, date, title of activity and its category, the exact timeframes of each activity and their duration time.

One more hidden feature is that you can add your Away time within a Timeline section. Just use the drag-and-drop method to create a timeframe and assign an activity.