Extension / Add on for IE, Chrome and Firefox

The full application will load content from a database and help user to fill a bunch of forms. I´m looking for a developer to do the browser extension especially for IE and Firefox, desirable for Chrome as well. I expect to receive both the app with the example below working and the source code to be modified and actually works with our project. WHAT IT´S BEING ASKED?? Add on for IE and Firefox - The add-on has to add an html code to some specified URLs. * Has to be able to add different HTMLs for each different specified URL. * The code and the URLs should be easily changed not by the user but by the developer. Example: 1) When user goes into www.freelancer.com The application should add "[login to view URL]("Hello freelancer!");" 2) When user goes into [login to view URL] The application should add "[login to view URL]("Hello googler!");"