Adobe Air Browser and Transparency

Question

Adobe

Not strong in Adobe Flash, Flex and Air, but I was interested in an example of a custom browser written in Air using the webkit engine:

www.adobe.com/devnet/air/flash/articles/air_browser_sample_application.html

The author writes and gives an example of a ready-made browser written in flash.

In addition to his code, I created another layer under the browser with a simple looping animation and tried for a long time to make this animation visible through the browser. But nothing happened.

Question: is it possible to remove the background in the "browser" component (HTMLPane) and make it transparent by default? If there is no overlay html content.

For work I used Adobe Flash Professional CS5 and the latest Abode Air at the moment. In the example, the code is written for CS4. The IDE suggested that I transform it automatically.