URL: http://www.engadget.com/2015/08/19/cochin-airport-runs-on-solar-power/
Browser / Version: Firefox Mobile 41.0
Operating System: Android 5.0.2
Problem type: Layout is messed up

Steps to Reproduce

1. Navigate to: http://www.engadget.com/2015/08/19/cochin-airport-runs-on-solar-power/
2. start scrolling down slowly
3. the fixed grey header bar shifts it's position for a certain distance and then returns to the top area after a certain scroll distance.

Expected Behavior:
Header bar should stay fixed floating on the top

Actual Behavior:
Header bar shifts it's position for some scroll distance.