--- a/browser/tools/mozscreenshots/mozscreenshots/extension/configurations/PermissionPrompts.jsm
+++ b/browser/tools/mozscreenshots/mozscreenshots/extension/configurations/PermissionPrompts.jsm
@@ -19,16 +19,17 @@ let lastTab = null;
 
 this.PermissionPrompts = {
   init(libDir) {
     Services.prefs.setBoolPref("media.navigator.permission.fake", true);
     Services.prefs.setBoolPref("media.getusermedia.screensharing.allow_on_old_platforms", true);
     Services.prefs.setCharPref("media.getusermedia.screensharing.allowed_domains",
                                "test1.example.com");
     Services.prefs.setBoolPref("extensions.install.requireBuiltInCerts", false);
+    Services.prefs.setBoolPref("signon.rememberSignons", true);
   },
 
   configurations: {
     shareDevices: {
       applyConfig: Task.async(function*() {
         yield closeLastTab();
         yield clickOn("#webRTC-shareDevices");
       }),