diff --git a/browser/themes/shared/incontentprefs/privacy.css b/browser/themes/shared/incontentprefs/privacy.css
index fd28fb6cd836f99a0406e9c660e835629e2aa425..781836068d7f3f9820f9519e5386145bdeb37f5a 100644
--- a/browser/themes/shared/incontentprefs/privacy.css
+++ b/browser/themes/shared/incontentprefs/privacy.css
@@ -132,8 +132,7 @@
   margin-top: 0.75em;
 }
 
-#blockCookiesCBDeck:not([selectedIndex]),
-#blockCookiesCBDeck:not([selectedIndex="0"]) {
+#blockCookiesCBDeck[selectedIndex]:not([selectedIndex="0"]) {
   max-width: 444px;
 }