diff --git a/BrowseWebsitesWithoutLoggingIn.txt b/BrowseWebsitesWithoutLoggingIn.txt
index a04044722..e575a15c2 100644
--- a/BrowseWebsitesWithoutLoggingIn.txt
+++ b/BrowseWebsitesWithoutLoggingIn.txt
@@ -61,4 +61,4 @@ ooopic.com###public-mask-login
 reddit.com##.listingsignupbar.infobar
 
 ! Stack Exchange
-stackexchange.com,askubuntu.com,serverfault.com,superuser.com##.js-dismissable-hero:has-text(Sign up)
+stackexchange.com,askubuntu.com,serverfault.com,superuser.com,mathoverflow.net,stackapps.com,##.js-dismissable-hero:has-text(Sign up)