# Extension ### Introduction Extension is an advanced function for Messenger platform. When a button’s hyperlink is connected with a website, you can select the prompt action to be an “extension”. Then when a customer clicks on the button, a website will be displayed directly on the current tab as an extension. This will not open any new windows or new tabs. {% hint style="success" %} When using “Extension” function, the linked website only needs support for mobile devices. There’s no need for an extra desktop version of the website. {% endhint %} ![](https://4036424674-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LlAIFssOEGqft8svll9%2F-LnpyrRTLiEeqYTmmR4H%2F-LnpyugSOq9e4lhtvnpt%2FExtension-1.png?alt=media\&token=09eab542-9d33-4f27-ab59-c6b7bf9603ab) ![](https://4036424674-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LlAIFssOEGqft8svll9%2F-LnpzIW0juCly9iDmV0c%2F-LnpzLphZIDUmLHip-8H%2FExtension-2.png?alt=media\&token=e5415f64-d6ec-405d-89dc-85caca201bd0) {% hint style="info" %} Currently, websites need to meet the standards of the Messenger Extension SDK in order to be used as extension windows. {% endhint %} For more detail and official documentation, visit