diff --git a/user.js b/user.js
index e220106..36e41b9 100644
--- a/user.js
+++ b/user.js
@@ -645,8 +645,9 @@ user_pref("browser.offline-apps.notify", true);
 user_pref("javascript.options.asmjs", false);
 // -------------------------------------
 // Disable Ion and baseline JIT to harden against JS exploits
-// user_pref("javascript.options.ion", false);
-// user_pref("javascript.options.baselinejit", false);
+user_pref("javascript.options.ion", false);
+user_pref("javascript.options.baselinejit", false);
+user_pref("javascript.options.native_regexp", false);
 // -------------------------------------
 // Disable WebAssembly
 user_pref("javascript.options.wasm", false);
@@ -700,7 +701,7 @@ user_pref("browser.pagethumbnails.capturing_disabled", true); // [HIDDEN PREF]
 user_pref("devtools.chrome.enabled", false);
 // -------------------------------------
 // Disable MathML (Mathematical Markup Language)
-// user_pref("mathml.disabled", true);
+user_pref("mathml.disabled", true);
 // -------------------------------------
 // Disable middle mouse click opening links from clipboard
 user_pref("middlemouse.contentLoadURL", false);