diff --git a/docs/api/webview-tag.md b/docs/api/webview-tag.md
index 63229a0b858..bc81fa8ed6d 100644
--- a/docs/api/webview-tag.md
+++ b/docs/api/webview-tag.md
@@ -184,6 +184,8 @@ page is loaded, use the `setUserAgent` method to change the user agent.
 A `boolean`. When this attribute is present the guest page will have web security disabled.
 Web security is enabled by default.
 
+This value can only be modified before the first navigation.
+
 ### `partition`
 
 ```html