On January 3, 2018, there was a fundamental flaw discovered with the CPU architecture we've been using for the past 20 years. This has shaken modern security to its roots. While the workings of Spectre and Meltdown are highly complicated (and deeply interesting, if you like the security field), what you have to know right now is that because of Spectre, all major browser vendors have disabled SharedArrayBuffer in browsers by default.
You can enable SharedArrayBuffer by going to chrome://flags and searching for SharedArrayBuffer and enabling it.
The reason for disabling SharedArrayBuffer is to mitigate Spectre, which is a dangerous but beautifully crafted exploit which requires a very precise measurement of time to attack. SharedArrayBuffer provides a way for multiple threads to be accessible to every thread, and atomics add more precision over...