Allow clipboard-write for iframe on Obsidian Publish

Is there any way to allow clipboard-write for iframe on Obsidian Publish? I have some iframe with copy button, It works in Firefox and Safari but not Chrome. Here is the error message in Chrome:

The Clipboard API has been blocked because of a permissions policy applied to the current document

Since I am using custom domain with Cloudflare, I set a transform rule in Cloudflare by following this instruction Controlling browser features with Permissions Policy - Chrome Developers. I add a Permissions-Policy header to the response and use custom JavaScript to set allow attribute. All the tries are failed.