docs(security): clarify IonicSafeString usage with innerHTMLTemplatesEnabled (#2906)

Author: liamdebeasi

docs/techniques/security.md

@@ -82,6 +82,10 @@ Ionic Framework provides an application config option called `sanitizerEnabled`
 
 Developers can also choose to eject from the sanitizer in certain scenarios. Ionic Framework provides the `IonicSafeString` class that allows developers to do just that.
 
+:::note
+In order to bypass the sanitizer and use unsanitized custom HTML in the relevant Ionic components, `innerHTMLTemplatesEnabled` must be set to `true` in the Ionic config. See [Enabling Custom HTML Parsing](#enabling-custom-html-parsing-via-innerhtml) for more information.
+:::
+
 #### Usage
 
 ````mdx-code-block