When Facebook CEO Mark Zuckerberg told Wall Street in February that the company was looking for ways to "grow the ecosystem of video content" on its platform, he probably didn't have Steve Stephens in mind.
Stephens is a Cleveland, Ohio, resident accused of shooting an elderly man in the head, then uploading the video onto his Facebook page -- where it stayed for several hours -- before streaming his post-shooting activity on Facebook Live.
And Stephens, the subject of a police manhunt, is not alone in using Facebook Live to promote a gruesome act.
Other footage has recorded a suicide in India, an accidental shooting in Chicago and a standoff with police in Baltimore. The latter ended with the death of a woman whose account was suspended by Facebook at the request of the police department that shot her soon after.
While Facebook says it is quick to take such content down, these incidents are reminders of how much has changed for the company from a year ago, when only celebrities had access to the Live feature.
Now, as Zuckerberg prepares to deliver his keynote address at the company's annual developer conference Tuesday morning, he'll look out onto a world -- and a competitive landscape -- transformed from last year's confab.
While some of these changes are outside Zuckerberg's control, many have been driven by Facebook's inexorable efforts to deliver ever more sophisticated services, to stay ahead of its arch-rival, Alphabet, and its newest competitor, Snap.
Apart from the violence on Facebook live, here are other ways Zuckerberg's world has changed in 12 short months.