Oh, he handles this situation very poorly, no question about that. That doesn't change the fact that he and his team wrote the vast majority of the original code. The long list of contributors does not reflect that.
Anyways, it's frustrating that the author is kinda acting a bit scummy for something that might not have been even a problem. If he was a bit patient and had just got permission from those people beforehand... (I don't really think any of those 10 people would object to it since the commits aren't that big, unless one of them is a free software movement purist perhaps) And people generally agree on Mozilla's "95% author coverage" line so I think this controversy might have been a bit overblown.