How to reproduce:

• Put a grid inside a window and load many records to let you see the scrollbars.

• Scroll for a while (up-down / right-left), after some scrolling the scrollbars will disappear

Tested on MacOS 10.8.5 (with hiding system scrollbars mode) / Chrome (latest) and webkit


Here the fiddle:

https://fiddle.sencha.com/#fiddle/ch8