That's a fair point in that yes, JavaScript was nonstandard when it was first included in a web browser.

But it is an incorrect point in that the field has changed a lot, for the better - most or all browser vendors want to play nicely these days. Even Microsoft is supporting the standards process and implementing WebGL, for example. The principles guiding browser vendors are more like these which Google wrote for Blink:

http://www.chromium.org/blink#new-features

> In practice, we strive to ensure that the features we ship by default have open standards.

That was not the case 18 years ago, but thankfully it is today. 18 years ago it might have been common practice to just ship a new VM in a browser, but to do so today with no regards for the standards process would be unexpected and improper.