Hi there!!
I am interested in taking up your project of building add ons on all the top browsers that you require.
I'm a professional in website development (PHP, codeigniter, wordpress, joomla, e-commerce, MySQL, Javascript, Jquery, Ajax, HTML5, CSS) and thus can meet your requirements fully.
However before commencement of work I would discuss further on this project regarding exactly what kind of add ons you require. It would be thus nice to chat once regarding the time,cost frame and also the requirements clearly.
Would be awaited to hear & begin soon.
Thanks.