A nearly six-hour outage not only locked 3.5 billion people out of Facebook and its various owned platforms, but also affected games companies reliant on its services.
The company's entire suite of apps and websites was down from around 4pm to 10pm BST yesterday, according the BBC, with Facebook claiming this was due to issues caused by "configuration changes on the backbone routers that coordinate network traffic between our data centers."
In addition to its titular social network, Facebook also owns image-led social media platform Instagram and messaging service WhatsApp, both of which were also down. There are also reports the outage affected everything from Facebook employees' emails to their work passes that enabled them to enter company offices.
The incident also had a notable impact on the video games industry.
The most obvious example is the Facebook-owned Oculus, which has required new users to have a Facebook account since October 2020. It has also been reported that deleting a Facebook account wipes out any purchases made for Oculus' virtual reality headsets.
Meanwhile, games companies that allow users to login with their Facebook accounts, rather than registering one specific to the game, were also affected. Both Electronic Arts and Niantic acknowledged the issues experienced in FIFA Mobile and Pokémon Go.
In the update explaining the outage, Facebook wrote: "People and businesses around the world rely on us everyday to stay connected. We understand the impact outages like these have on people's lives, and our responsibility to keep people informed about disruptions to our services.
"We apologise to all those affected, and we're working to understand more about what happened today so we can continue to make our infrastructure more resilient."