Userscripts.org

Here's some sample code showing how you can get the html comments using xpath instead of regexp.

var htmlComments = document.evaluate(
				'//comment()', document, null,
				XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null
			);

for (var i = 0; i < htmlComments.snapshotLength; i++)
	GM_log('\nFound html comment:\n' + htmlComments.snapshotItem(i).data); // Log to console