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Every time you start working on a bug select this bug in the table and click the Work on Bug button 
in the bug toolbar or select Time | Work on Bug or press CTRL + G. The bug is will be tagged with the special icon 
and the time tracker window will appear.
The time tracker window shows the following information:
- How much time was spent on the bug in total
- The work status (working, paused, stopped). If the tracking is on, the Start Tracking button is selected and the window is colored green. If tracking is paused, both Start Tracking and Pause Tracking buttons are selected and the window is colored gray. If tracking is stopped, no buttons are selected and the window is colored red.
- Time of the last status change
- Time spent during last session
- Remaining time
- Bug number and summary
- Comments for the current session
If you plan to stop working on a bug for a while and then resume your work, click the Pause button or select Time | Pause Tracking. Click the Start Tracking button to resume.
If your want to stop working on the bug