# Firefox ## Build wrapped Firefox with extensions and policies The `wrapFirefox` function allows to pass policies, preferences and extension that are available to firefox. With the help of `fetchFirefoxAddon` this allows build a firefox version that already comes with addons pre-installed: ```nix { myFirefox = wrapFirefox firefox-unwrapped { extraExtensions = [ (fetchFirefoxAddon { name = "ublock"; url = "https://addons.mozilla.org/firefox/downloads/file/3679754/ublock_origin-1.31.0-an+fx.xpi"; sha256 = "1h768ljlh3pi23l27qp961v1hd0nbj2vasgy11bmcrlqp40zgvnr"; }) ]; extraPolicies = { CaptivePortal = false; DisableFirefoxStudies = true; DisablePocket = true; DisableTelemetry = true; DisableFirefoxAccounts = true; FirefoxHome = { Pocket = false; Snippets = false; }; UserMessaging = { ExtensionRecommendations = false; SkipOnboarding = true; }; }; extraPrefs = '' // Show more ssl cert infos lockPref("security.identityblock.show_extended_validation", true); ''; }; } ```