Credit: Tina Rowden / HBO
HTTP + WebSocket networking that never blocks the UI
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Topologically, Bobs world is a doughnut, and the road is a loop around the hole of the doughnut. If we were to stretch it (don’t worry, this wont harm Bob, he does not even notice!), we would get the following picture:
They pointed out that when a user sees a 550 error, they don't always realize the receiving mail server is refusing the message, instead assuming that their own ISP is blocking their outgoing email.