diff --git a/modules/desktop/browsers/firefox/default.nix b/modules/desktop/browsers/firefox/default.nix
index 6bf2535c..cc3b4aa5 100644
--- a/modules/desktop/browsers/firefox/default.nix
+++ b/modules/desktop/browsers/firefox/default.nix
@@ -12,8 +12,8 @@ in
     programs.firefox = {
       enable = true;
       preferences = {
-        toolkit.legacyUserProfileCustomizations.stylesheets = true;
-        browser.compactmode.show = true;
+        "toolkit.legacyUserProfileCustomizations.stylesheets" = true;
+        "browser.compactmode.show" = true;
       };
     };
   };