It took me a while to figure out what's going on. Here's my summary: This issue has been lodged on the github for the ECMAScript standard. It points out that t

It took me a while to figure out what's going on. Here's my summary: This issue has been lodged on the github for the ECMAScript standard. It points out that the HTML5 standard specifically states that they intentionally violate the ECMAScript standard by imbuing the 'document.all' object with special behavior. This issue asked the ECMAScript working group if there was any desire to formalize this exception in ECMAScript, and thereby modifying it to be in line with the behavior specified in HTML5. If that seems backwards, yes, it does to me too; but the issue thread has arguments either way.