[BUG #6609] Use collection API for content elements.
[BUG #6609] Fix appear event.
[BUG #6609] Added input website widget to use it in the desktop environment.
[BUG #6609] Added text selection module.
[BUG #6609] Move addListener from website widget to static registration addListener call
[BUG #6609] Fixed mouse capturing
Minor.
[BUG #7739] Added Ponints.js polyfill and changed some website widgets to use it.
[BUG #6609] Fixes in the playground.
Minor
Minor
[BUG #7739] Use pointer events instead of mouse events