See update at end of post. Mozilla comments that "a large amount of users" are refusing updates to Firefox because of Google's decision; meeting notes call this a "top support issue."

Update 2: See Mozilla comment at end of post.

Mozilla, you’ve just been dumped.

In a short blog post, Google has announced that it will no longer continue development of the Google Toolbar for Firefox. Here’s the entire text of that post:

An update on Google Toolbar for Firefox First of all, we'd like to thank all of our loyal users of Google Toolbar for Firefox. We deeply appreciate all of the feedback over the years that helped to make the product so useful. As we all know, over the past few years, there has been a tremendous amount of innovation in the browser space. For Firefox users, many features that were once offered by Google Toolbar for Firefox are now already built right into the browswer. [sic] Therefore, while Google Toolbar for Firefox works on versions up to and including Firefox 4 only, it will not be supported on Firefox 5 and future versions. Please see our Help Center for additional details.

Firefox 5, of course, is the current version, with Firefox 6 due in mid-August and Firefox 7 due a mere six weeks after that.

The kicker, though, is this line at the end of the post, which I have reprinted verbatim:

WRITTEN BY BRITTNEY

When Google announced yesterday that it was shutting down Google Labs, the blog post came from a Google senior vice president, Bill Coughran. The bearer of bad tidings for Firefox has no last name and no title--for all we know, Brittney is a Google intern.

Commenters are taking Brittney to task for her assurances that many of these features “are now already built right into the browser.” One offered up this list: “Spelling, custom buttons, Google bookmarks, translate, need I go on?”

The absence of a Google toolbar probably hurts Firefox even more in the pocketbook, given that the Mozilla Foundation (which leads the Mozilla project that in turn results in Firefox) through the years has received hefty commissions from Google for search referrals. The most recent Mozilla Foundation Annual Report (for 2009, last modified in November 2010) notes that the agreement with Google ends this year:

We have had a productive relationship with Google since 2004 and that relationship remains healthy. To date, we have renewed our contract three times, in 2005, 2006 and 2008. The current version extends through 2011. We believe that search providers will remain a solid generator of revenue for Mozilla for the foreseeable future.

It's worth remembering that just a few years ago, before the rise of Chrome, Firefox actually distributed its browser third parties distributed Firefox as a bundle with the Google toolbar, and Google paid a commission for every toolbar installed.

The Firefox team has already told enterprise customers (who in a parallel universe would be a source of revenue) that Firefox isn’t for them. They’ve tried a bit of damage control, including this vague announcement from earlier this week:

Mozilla is fundamentally about people and we care about our users wherever they are. To this end, we are re-establishing a Mozilla Enterprise User Working Group as a place for enterprise developers, IT staff and Firefox developers to discuss the challenges, ideas and best practices for deploying Firefox in the enterprise.

Meetings scheduled, talks to be held, but no commitment for any actions. Color me skeptical about this initiative.

Meanwhile, Firefox is continuing to lose market share, mostly to Google’s Chrome (see Google Chrome continues its rapid rise, IE and Firefox fall). Earlier this year, I predicted that Internet Explorer will survive but Firefox won’t. If the cash spigot from Google is turned off, Mozilla’s future becomes uncertain at best.

Update 7-22 10:30AM PDT: Several commenters have suggested this is a non-issue, that no one uses toolbars. That's not what Mozilla says. CNET's Stephen Shankland discovered otherwise, digging up notes from Mozilla that suggest the issue is affecting a significant number of customers:

"We know that a large amount of users are not taking update offers to 5+ due to Google Toolbar incompatibility," said Firefox release manager Christian Legnitto in meeting notes. "Many users likely expect a new version of Google toolbar to be released and marked compatible." [Emphasis added]

He said Mozilla has two problems: telling people the toolbar won't arrive and helping them extract whatever data they have stored with it. But there's not much time to respond if Mozilla wants to act fast.

In those same notes, Mozilla also says "Google Toolbar incompatibility is a top support issue," adding:

One major issue is that people saved bookmarks with the toolbar. They should be available on www.google.com/bookmarks, but people may not be aware of this?!

In small print at the end of those notes, Mozilla acknowledges the need to "tell [Firefox users] the toolbar is gone and not coming back."

Update 29-July: via e-mail a Mozilla spokesperson responds:

The Google Toolbar for Firefox is not in any way connected to the search arrangement between Mozilla and Google which continues to be a strong and mutually beneficial partnership. This toolbar was developed by Google as their own independent product, distributed and marketed by them. As the most customizable browser, Firefox has thousands of free add-ons available through addons.mozilla.org, including many that provide similar functionality to the now defunct Google Toolbar.

Mozilla declined to respond to follow-up questions about whether the search deal with Google, which ends in 2011, will be renewed.