Changes

The Chrome extension API was designed to work well with process separation and we are certainly taking inspiration from it and copying functionality where it makes sense. However, there will be differences. We won't implement all of Chrome's APIs. And Chrome is unlikely to implement some of the APIs we add. Imagine the APIs as a [https://en.wikipedia.org/wiki/Venn_diagram Venn diagram]. In the middle are cross-browser APIs for content scripts, tabs, and windows. In the Firefox side are APIs for toolbars and sidebars. On the Chrome side are APIs for Google's cloud services.