diff --git a/home/applications/firefox/default.nix b/home/applications/firefox/default.nix
index ca24e34..e30b333 100644
--- a/home/applications/firefox/default.nix
+++ b/home/applications/firefox/default.nix
@@ -4,11 +4,13 @@
     enable = true;
     package = pkgs.firefox.override {
       extraPrefsFiles = [
-        "${pkgs.arkenfox-userjs}/user.cfg"
         (pkgs.runCommandLocal "userjs" { } ''
-          install -Dm644 ${./user-overrides.js} $out
-          substituteInPlace $out \
-            --replace-fail "user_pref" "defaultPref"
+          substitute ${pkgs.arkenfox-userjs}/user.js $out \
+            --replace-fail 'user_pref' 'lockPref'
+        '')
+        (pkgs.runCommandLocal "userjs" { } ''
+          substitute ${./user-overrides.js} $out \
+            --replace-fail 'user_pref' 'lockPref'
         '')
       ];
     };
diff --git a/home/applications/firefox/user-overrides.js b/home/applications/firefox/user-overrides.js
index 1ae7ca5..1e4e077 100644
--- a/home/applications/firefox/user-overrides.js
+++ b/home/applications/firefox/user-overrides.js
@@ -22,6 +22,7 @@ user_pref("signon.rememberSignons", false);
 // Neat features, nice to have
 user_pref("browser.compactmode.show", true);
 user_pref("browser.search.separatePrivateDefault", false);
+user_pref("browser.tabs.hoverPreview.enabled", true);
 user_pref("browser.tabs.inTitlebar", 0);
 user_pref("browser.urlbar.suggest.calculator", true);