How is the panel displayed when launching Chrome Hangout extension made to be always on top and pinned?

Question

When launching the Chrome Extension Google-Hangouts, a panel initially appears that lists members and a link/button to create a new Hangout.

This panel is initially pinned to the bottom right of the browser window. When pinned like this, it remains always on top as a browser navigation session continues: users can go to different URLs, change tabs, etc. and that panel stays at the bottom right and stays on top of all other windows (or at least on top of the main browser window).

Once it's unpinned, you can drag it around the window, but it no longer stays always on top.

My question is, how was that achieved - what code, or what functions, do i need to call to create that window/panel so that it stays initially pinned and always on top? Is there some binding to some native code that's involved? Some other approach?

If anyone know and can show or explain, i would be hugely grateful as this feature is key to an extension i'm trying to build.

Thanks a lot!

Answer 1

This may not be an answer but to get a clue of what is happening I extracted the crx file to view its content there are a few OS specific files : ace.dll , libace.so and ace. After researching a bit i found this. This is a plugin. Hangouts extension is using ace plugin which is actually running on your desktop(i'm not sure about this). You can check this article

Answer 2

I found this related post: How to build an chrome extension like Google Hangouts

ACE is actually not what makes the window, Chrome has that capability built in, apparently. Even if you don't enable panels, extensions from Google can still make them, provided your OS is capable.