diff --git a/Optional-Hardening.md b/Optional-Hardening.md
index 4d592eb..80f2317 100644
--- a/Optional-Hardening.md
+++ b/Optional-Hardening.md
@@ -87,6 +87,20 @@ user_pref("dom.security.https_only_mode_error_page_user_suggestions", true);
 
 ***
 
+### Captive portal detection
+Captive portals allow you to connect to public Wi-Fi by redirecting to login pages (think hotels, airports, etc.). You can safely disable Mozilla's [captive portal detection](https://support.mozilla.org/en-US/kb/captive-portal) on a **desktop** computer. 
+
+If you disable captive portals on a **mobile** device, then you'll need a separate browser to connect to the internet on public Wi-Fi and some [company networks](https://github.com/yokoffing/Betterfox/discussions/377).
+
+```javascript
+// PREF: disable captive portal detection
+user_pref("captivedetect.canonicalURL", ""); 
+user_pref("network.captive-portal-service.enabled", false); 
+user_pref("network.connectivity-service.enabled", false); 
+```
+
+***
+
 ### Secure DNS
 Setup and enforce [DNS-over-HTTPS](https://support.mozilla.org/en-US/kb/firefox-dns-over-https) (DoH).