diff --git a/src/extension.js b/src/extension.js
index 0814127..5e1412d 100644
--- a/src/extension.js
+++ b/src/extension.js
@@ -68,7 +68,9 @@ function enable() {
 }
 
 function disable() {
-	proxy.disconnect(proxy_connect_id);
+	if ( proxy && proxy_connect_id ) {
+		proxy.disconnect(proxy_connect_id);
+	}
 
 	_set_theme(original_user_theme);