One by one:

I would argue you're not the public face of the company until you are the CEO, or a PR officer. While your primary job is involved with engineering or architecture, you have a technical role, but as CEO your role shifts to become primarily political and managerial. These roles do of course all blend together at smaller companies, but the spotlight appears certainly the moment you assume the mantle of CEO. You are right I don't know the history by heart (certainly not as well as you do) but I think there's an argument to be made that in most companies there is significantly less concern about the politics/personal beliefs of non-CEO employees than the appointed public face.

While I certainly agree the donation doesn't fit the legal definition, I'd say it falls under a very sane definition of hate speech, at least in the context under which the proposition existed at the time and the movement it represented. Prop 8 was an initiative designed as a symbolic gesture by anti-gay (read: hate) activists to codify in law the explicit removal ("re-removal", in the words of the judge who ruled on it) of rights from a marginalized group of people. Vocal support for it is hate speech. Monetary support is similar but more extreme. I don't think this characterization is far off though I will admit it is unnecessarily incendiary because of the unintended conflation with the legal term. So I will give you this; it is a speech action, and it is hateful, but I shouldn't have characterized it as hate speech.

And for many "take your rights away" exactly characterizes this initiative. Though in California domestic partnerships exist which give the same rights as a marriage, it's codifying in law that a gay relationship is 'less than' a straight relationship. Removing the actual rights associated with the partnership happens to be politically untenable in California, though it isn't in many other states and so they have done exactly this; prop 8 was a symbolic gesture to many that said "We can't take your rights away much as we'd like to, but remember there are still a whole lot of anti-gay people in California".

And since writing my original post I learned more about the history of the incident, read your blog post on inclusiveness in response to the incident which I found very passionate and compelling and changed my mind; I am still vehemently opposed to prop 8 or any measure like it and I still think it's a hateful and ugly thing to support, and that the public face of a company that supports inclusiveness has no business issuing public statements in favor of it, but I agree you were victimized by a crusade, the boycott was out of line and inappropriate, and have no problem with the appointment.

So many news stories pass us by and all we retain from them are snippets of blogspam or clickbait articles or comments on social media and we all get our own impressions of how things occurred, often times they are horribly distorted one-sided glimpses we have into the histories of actual events. I think in general people in this age, myself especially included, are too quick to condemn in situations they don't fully understand so I apologize and I appreciate all the work you've done for Mozilla, and freedom and openness on the internet.