Clipboard plain text+HTML+GFM demo

Demo for https://github.com/orgs/community/discussions/65235

HTML

<p>
Demo for <a href="https://github.com/orgs/community/discussions/65235">a discussion on GitHub</a>.
</p>
<p>
<button onclick="copy(event);">Press me to copy</button>
</p>

JavaScript

function copy(e) {
	e.preventDefault();
	const plainText = "plain text: example.net";
	const html = 'HTML: <a href="https://example.net">example.net</a>';
	const gfm = "GFM: [example.net](https://example.net)";
	const handleCopyEvent = event => {
		event.stopPropagation();
		event.preventDefault();
		const clipboardData = event.clipboardData || window.clipboardData;
		clipboardData.setData('text/plain', plainText);
		clipboardData.setData('text/html', html);
		clipboardData.setData('text/x-gfm', gfm);
	};
	document.addEventListener('copy', handleCopyEvent);
	document.execCommand('copy');
	document.removeEventListener('copy', handleCopyEvent);
}