Frameset Encapsulator is a free Chrome add-on developed by Kanade Tokaimori. It provides a solution for websites that still use legacy HTML framesets by encapsulating them within an iframe. This allows certain extensions to function properly on frame-based websites from the past.

With Frameset Encapsulator, users can ensure that frame-based websites, which may not be compatible with modern browsers, can still be accessed and used without any issues. By encapsulating the frameset within an iframe, this add-on enables the correct functioning of extensions that were not designed to work with framesets.

This tool is particularly useful for those who frequently encounter frame-based websites from the old days and rely on extensions to enhance their browsing experience. Frameset Encapsulator provides a simple and effective solution to make these websites compatible with modern browsers, ensuring a seamless user experience.