Check for #8984 wasn't strong enough, enhanced.

src/core.js

@@ -96,7 +96,7 @@ jQuery.fn = jQuery.prototype = {
 		// Handle HTML strings
 		if ( typeof selector === "string" ) {
 			// Are we dealing with HTML string or an ID?
-			if ( selector.charAt(0) === "<" || selector.charAt( selector.length - 1 ) === ">" ) {
+			if ( selector.charAt(0) === "<" && selector.charAt( selector.length - 1 ) === ">" && selector.length >= 3 ) {
 				// Assume that strings that start and end with <> are HTML and skip the regex check
 				match = [ null, selector, null ];