I've been a bit worried on how much we depend on Zuck's apps for a while. Alas, the two branchs of my family (in Italy and in Venezuela), most of my friends and pretty much all of my pupils communicate with me using either FB, Whatsapp or, to a lesser extent, Instagram and Messenger. Even the neighbours of the building where I live communicate via a WA group. Yes, well, I have accounts on Signal, Telegram, Discord, etc -but they don't and inertia keeps things as they are. And then we get yesterday's outage. And, interestingly, the congressional testimony. I wasn't gloating (as many were on twitter) for losing access to these apps. But I will be pushing a little harder for alternatives, futile as that endeavour may seem.
A rather technical explanation of what happens, here:
https://blog.cloudflare.com/october-2021-facebook-outage/
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