Stephen Shankland/CNET

Another major management change is coming to Firefox as Johnathan Nightingale, the vice president who oversees the open-source Web browser project, will leave Mozilla on March 31.

In a blog post Tuesday, Nightingale said Mozilla made it through a rough patch last year and that he's making the change to tighten ties with his family and with the tech scene in Toronto, where he lives.

"No, I haven't been poached by Facebook. I don't actually know what my next thing will be," said Nightingale, who joined Mozilla in 2007. "I want to take some time to catch up on what's happened in the world around me. I want to take some time with my kid before she finishes her too-fast sprint to adulthood. I want to plant deeper roots in Toronto tech, which is incredibly exciting right now and may be a place where I can help."

The change comes less than a year after Mozilla endured a traumatic management change. Co-founder and Chief Technology Officer Brendan Eich was promoted to chief executive, but lasted less than two weeks because of a firestorm of controversy around his earlier opposition to gay-marriage rights. After he resigned, Mozilla rehired Chris Beard, who earlier had led Firefox marketing work, to fill the CEO post.

Replacing Nightingale will be Mark Mayo, who for the last four years has led Mozilla's cloud services group, a responsibility he'll keep with the new title vice president and general manager of Firefox.

Nightingale strenuously denied in his resignation note to Mozilla staff that his departure is the "sign of doom" that some will take it to be. "Predictable, and dead wrong; it misunderstands us completely. When things looked really rough, at the beginning of 2014, say, and people wanted to write about rats and sinking ships, that's when I, and all of you, stayed," Nightingale said in the blog post.

Regardless, it'll mean more change for Firefox, and that change comes at a hard time for Mozilla. With Firefox and its close cousin, Firefox OS, Mozilla is fighting hard to compete with Chrome and Internet Explorer on personal computers and fighting harder to gain even a small foothold on the faster-growing future of smartphones and tablets. The relevance Mozilla enjoyed a decade ago supplying a nimbler, more secure, more competitive alternative to Internet Explorer is much harder to come by these days.

New Firefox leader

Mayo, who joined Mozilla in 2011 after serving as chief technology officer for Joyent and a leader of the Node.js project, will take over Firefox as part of a Mozilla unification of two groups.

Mozilla

"Today we combined our group focused on cloud services with the group focused on our Firefox desktop and mobile browsers," Beard said in a statement. "Recently we have been exploring how we can integrate client software on desktops and mobile with cloud service approaches to evolve what Firefox can do for people. In an effort to support this vision, it's a great time to hand over leadership to someone deeply experienced in mobile and cloud services."

Those cloud services include the Firefox Marketplace app store, the Hello online chat technology now in Firefox, and the related Firefox Accounts and sync tools to carry a person's identity and preferences across Firefox and Firefox OS.

Beard praised Nightingale for "eight years of distinguished service" and thanked him "for his countless contributions to the Mozilla project and leading Firefox through periods of intense competition and change."

Beard said Firefox "turned a corner" in the last year. "We achieved positive growth again and dramatically reset our global search strategy -- and we now have a much stronger foundation from which to build, grow and pursue our mission."

Nightingale didn't immediately respond to a request for comment.

Other departures

There have been other personnel changes, too, since Beard took over. Tristan Nitot, a 17-year Mozilla employee who founded Mozilla Europe, left earlier this month to write a book. And developer relations staff have seen a lot of turnover. Christian Heilmann, formerly Mozilla's principal developer evangelist, joined Microsoft in January as a senior program manager advocating Web standards. Frédéric Harper, a Mozilla technical evangelist, left in October to lead developer relations at Mashape.

And Robert Nyman, another Mozilla technical evangelist, joined Google to run developer relations for Nordic countries. "Mozilla is going through a number of challenges at the moment, and to be honest, it's my belief that the upper management need to acknowledge and address these," Nyman said.

Mozilla is a large organization, with more than 900 people in the for-profit entity at the core of the broader non-profit organization.

It largely accomplished its original mission with Firefox -- ensuring that people had a choice of browsers to use the Web, not just Microsoft's Internet Explorer, which was dominant a decade ago, and that those browsers delivered Web technology through standards rather than proprietary extensions to the Web. Indeed, with the arrival of Google's Chrome, Microsoft's active engagement with the Web's future, and the spread of the Web to mobile devices, standards have arguably never been more important to the Web.

Nightingale said things are looking up for Firefox. From the blog post:

But Mozilla today is stronger than I've seen it in a long time. Our new strategy in search Firefox on iOS



Updated at 1:37 p.m. PT with comment from Beard and details about Mark Mayo replacing Nightingale as the top Firefox executive.