Facebook sprung a surprise on Thursday when Mark Zuckerberg revealed that another of his essential lieutenants was leaving the business.

Following the departure of senior executives such as Instagram cofounders Kevin Systrom and Mike Krieger, Zuckerberg stated primary item officer Chris Cox is headed for the door after 13 years Chris Daniels, the head of WhatsApp, is likewise leaving.

Not long after whatever was main, Cox released his bye-bye letter to personnel on his Facebook page On very first read, it’s an ode to his great times at the business, in which he applauds the senior management group and calls Zuckerberg a “dear pal.”

In the remarks listed below, there are radiant homages from Zuckerberg (” It’s been an honor and I’m deeply grateful”), COO Sheryl Sandberg (” We are a much better business for what you have actually provided”), and CTO Mike Schroepfer (” I’ll deeply miss out on seeing you ever [sic] day).

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However there’s an informing line in Cox’s letter which signifies that there were disputes over the instructions Zuckerberg is taking Facebook— particularly, its pivot to personal privacy and file encryption, which the CEO set out in a manifesto recently.

Here’s the essential line from Cox’s note:

“As Mark has actually laid out, we are turning a brand-new page in our item instructions, concentrated on an encrypted, interoperable, messaging network.

“It’s an item vision attuned to the subject these days: a contemporary interactions platform that stabilizes expression, security, security, and personal privacy.

“This will be a huge task and we will require leaders who are delighted to see the brand-new instructions through.”

This last sentence is exposing. By stating Zuckerberg’s vision will require individuals who think in the instructions of travel, it suggests that Cox is not amongst them.

Undoubtedly, The New york city Times reports that there were “disputes” over Zuckerberg’s strategy, which in essence will integrate the backends of WhatsApp, Messenger, and Instagram messaging to develop an interoperable messaging service, safeguarded by end-to-end file encryption.

Pointing out 6 sources, the Times reported that Cox “disagreed with a few of Mr. Zuckerberg’s item concepts and modifications, consisting of the ‘merged messaging’ task planned to link the apps.”

This was echoed by Ben Horowitz, the cofounder of prominent Silicon Valley VC company Andreessen Horowitz. Horowitz’s partner, Marc Andreessen, is a Facebook board member.

Horowitz tweeted that the departures of Cox and Daniels reveal there is “incredibly strong dissent” over Zuckerberg’s vision for Facebook. He included that it’s a big turnabout and “is rather clear that the choice was enormously questionable.”