Browser extension

A browser extension is a plug-in that extends the functionality of a web browser in some way. Some extensions are authored using web technologies such as HTML, JavaScript, and CSS. Browser extensions can change the user interface of the web browser without directly affecting viewable content of a web page; for example, by adding a "toolbar."

History

Internet Explorer started supporting extensions from version 5 released in 1999.Firefox has supported extensions since its launch in 2004. The Opera desktop web browser supported extensions from version 10 released in 2009. Google Chrome started supporting extensions from version 4 released in 2010. The Safari web browser started supporting native extensions from version 5 released in 2010. The syntax for extensions may be quite different from browser to browser, or at least different enough that an extension working on one browser does not work on another. As for search engine tools, an attempt to bypass this problem is the multitag strategy proposed by the project Mycroft, a database of search engine addons working on different browsers.