You keep using that word. I do not think it means what you think it means. From Wikipedia:
"""Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering."""
Nothing of this applies to Pepper API or NaCl. Mozilla can implement Pepper API and NaCl or can even just take NaCl as whole because it is, oh boy, oh boy, open source with a permissive license.
Please forgive me if I am wrong but JavaScript was not an "open standard" either in the beginning. It took you 1 year to submit it to the ECMA body for consideration. And, oh boy, you are still fixing JS design mistakes with a group of quite smart engineers and computer scientists.
Now lets step back and look into the past: was JavaScript implementation or specification as open to comments and feedback as Dart is now? There are public mailing lists, issue tracker and open repositories that accept patches and suggestions. Did you have that for JavaScript?
I might be utterly wrong but I bet you did not. Yet instead of participating in the language effort or at least stepping back and patiently watching it's birth and growth into something standardizable you criticize and bash it.
You keep using that word. I do not think it means what you think it means. From Wikipedia:
"""Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering."""
Nothing of this applies to Pepper API or NaCl. Mozilla can implement Pepper API and NaCl or can even just take NaCl as whole because it is, oh boy, oh boy, open source with a permissive license.