I just love playing with my phone settings, when I discovered this advanced settings on my device.

Follow procedure accordingly to try it out;

1. Swipe down your notification bar, Tap and hold on gear settings icon.
You will receive a congratulations message

2. Scroll down to system UI tuner.

3. Open and you will see some advanced settings 

4. In my case I open status bar to set seconds timer. 
Note: There are other settings there, just be careful with changes you made. 

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