diff --git a/browser/app/profile/firefox.js b/browser/app/profile/firefox.js
index a90e5fec1ac6..fe549823f9ae 100644
--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -1026,6 +1026,7 @@ pref("services.sync.prefs.sync.privacy.clearOnShutdown.offlineApps", true);
 pref("services.sync.prefs.sync.privacy.clearOnShutdown.passwords", true);
 pref("services.sync.prefs.sync.privacy.clearOnShutdown.sessions", true);
 pref("services.sync.prefs.sync.privacy.clearOnShutdown.siteSettings", true);
+pref("services.sync.prefs.sync.privacy.donottrackheader.enabled", true);
 pref("services.sync.prefs.sync.privacy.sanitize.sanitizeOnShutdown", true);
 pref("services.sync.prefs.sync.security.OCSP.disable_button.managecrl", true);
 pref("services.sync.prefs.sync.security.OCSP.enabled", true);