Why is "active" support relevant. Surely it is his views that make so many uneasy.
> 2. The CEO is the public face of Mozilla, and to some extent sets the agenda.
This is true, but of what relevance? Mozilla is not an organisation with an agenda about marriage or LGBTQ rights.
> 3. There are quite a number of developers and others in the community, some of whom work at Mozilla, who are either in or will consider a same-sex marriage at some point in the future.
I expect there are also some Mormons and Muslims who may wish to practice polygamy, perhaps even some Jews who feel obliged to enter in to a levirate marriage despite already being married. I suspect that any alternative CEO would probably support monogamous marriages only. Presumably the board must enquire as to any candidate's opinion on this matter and woe betide any CEO anywhere who doesn't support polygamy. They too could be in for this kind of treatment.
> 4. These people are disappointed (reasonably so) that a person who is campaigning against their civil rights has been appointed to a relatively important and visible position.
Brendan Eich is not and never has campaigned against their civil rights. Furthermore, before this appointment Brendan Eich already held a "relatively important and visible position." Brendan Eich simply donated money towards a campaign that he supported for reasons we do not know. He was joined in his view by a MAJORITY of voters at that time.