Tech workers at companies including Facebook, Google, and Amazon.com Inc have pursued social justice issues in recent years, urging the companies to change policies.
Employees "recognize the pain many of our people are feeling right now, especially our Black community," Stone wrote in a text.
"We encourage employees to speak openly when they disagree with leadership. As we face additional difficult decisions around content ahead, we'll continue seeking their honest feedback."
Last week, nationwide unrest erupted after the death of a black man, George Floyd, in police custody in Minneapolis last Monday. Video footage showed a white officer kneeling on Floyd's neck for nearly nine minutes before he died.
On Friday, Twitter Inc affixed a warning label to a Trump tweet that included the phrase "when the looting starts, the shooting starts." Twitter said it violated rules against glorifying violence but was left up as a public interest exception.
Facebook declined to act on the same message, and Zuckerberg sought to distance his company from the fight between the president and Twitter.
On Friday, Zuckerberg said in a Facebook post that while he found Trump's remarks "deeply offensive," they did not violate company policy against incitements to violence and people should know whether the government was planning to deploy force.
Zuckerberg's post also said Facebook had been in touch with the White House to explain its policies.
Jason Toff, a director of product management and former head of short-form video app Vine, was one of several Facebook employees organizing fundraisers for racial justice groups in Minnesota. Zuckerberg wrote on Facebook on Monday the company would contribute an additional $10 million to social justice causes.
Toff tweeted: "I work at Facebook and I am not proud of how we're showing up. The majority of coworkers I've spoken to feel the same way. We are making our voice heard."
