Write some Software

The requirements are as follows: - The extension will detect the page that has been blocked by the isp (detect by page connection reset or page no content loaded) and redirect the user to another Alternative url. If the alternative url is blocked then will redirect to the next alternative url. - The extension will be installed to Firefox Portable Version (Windows, Mac). Please make sure the extension it works for both version. - Ability to push updates. Able to auto update the list of main url and alternative url whenever the browser is started. The list of main url and alternative url will be loaded from a external JSON url. (sample json format attached). The JSON url to retrieve the list is hardcoded inside the extension. - The extension must able to prompt user if there's any new update to the extension. (Please advice on how to do this) Links [login to view URL] (firefox portable windows version) [login to view URL] (firefox portable mac version)