Firefox allowed for a sandbox security model to manage privileges accorded to JavaScript code, but that feature has since been deprecated.[82] It limits scripts from accessing data from other websites based on the same-origin policy.[83] It also provides support for smart cards to web applications, for authentication purposes.[84] It uses TLS to protect communications with web servers using strong cryptography when using the HTTPS protocol.[85] The freely available HTTPS Everywhere add-on enforces HTTPS, even if a regular HTTP URL is entered.