diff --git a/src/browser/provider/built-in/firefox/runtime-info.js b/src/browser/provider/built-in/firefox/runtime-info.js
index 02c6971808e..72f459411a2 100644
--- a/src/browser/provider/built-in/firefox/runtime-info.js
+++ b/src/browser/provider/built-in/firefox/runtime-info.js
@@ -35,7 +35,7 @@ async function generatePrefs (profileDir, port) {
         'user_pref("datareporting.healthreport.service.firstRun", false);',
         'user_pref("datareporting.policy.dataSubmissionEnabled", false);',
         'user_pref("datareporting.policy.dataSubmissionPolicyBypassNotification", true);',
-        'user_pref("app.shield.optoutstudies.enabled", false);'
+        'user_pref("app.shield.optoutstudies.enabled", false);',
         'user_pref("extensions.shield-recipe-client.enabled", false);',
         'user_pref("extensions.shield-recipe-client.first_run", false);',
         'user_pref("extensions.shield-recipe-client.startupExperimentPrefs.browser.newtabpage.activity-stream.enabled", false);',