How can I add extension to browser from ExtJs application?

Which browser(s) is most comfortable for add-on/extension development and why?

• What are some common pitfalls when expanding a particular browser? What are some methods a developer can use to hook in dynamic data? Are there any companies or studios that specialize in browser add-on development?

• Answer:

  I really prefer to develop for Chrome than Firefox. It's really easy in Chrome to use the developer mode and load unpacked extension, reload them after changes without having to reload the browser (it's not possible in Firefox...). The documentation is crystal clear with some very good samples and you can also broadcast your beta extension to a limited number of trusted users with Chrome Web Store. The inline installation to make the users install your extension directly from your website is also super cool. You already have some methods to detect if the user has your extension already installed or not. Something that Firefox doesn't provide. Edit: Oh and Chrome supports Greasemonkey scripts without any others extensions now, that's also super awesome.