diff --git a/dom/security/test/general/browser.ini b/dom/security/test/general/browser.ini
index 05b1df20f946..e063df2a9d6e 100644
--- a/dom/security/test/general/browser.ini
+++ b/dom/security/test/general/browser.ini
@@ -17,7 +17,7 @@ support-files =
 support-files =
   file_FTP_console_warning.html
 [browser_test_assert_systemprincipal_documents.js]
-skip-if !nightly_build
+skip-if = !nightly_build
 support-files =
   file_assert_systemprincipal_documents.html
   file_assert_systemprincipal_documents_iframe.html