> With performance.now() -- its not a clock but a counter and browsers can intentionally limit its accuracy to make 'fingerprinting' harder. The primary reason

> With performance.now() -- its not a clock but a counter and browsers can intentionally limit its accuracy to make 'fingerprinting' harder. The primary reason that performance.now()'s precision is limited is for security reasons. Spectre showed that it was possible to perform timing attacks to leak other memory on the system, and having a browser leak memory from other processes is quite a dangerous attack. As part of spectre's mitigations, browsers began limiting performance.now()'s precision. See docs on this: https://developer.mozilla.org/en-US/docs/Web/API/Performance/now https://developer.mozilla.org/en-US/docs/Web/API/Performance... Chromium's impl: https://chromium-review.googlesource.com/c/chromium/src/+/853505 https://chromium-review.googlesource.com/c/chromium/src/+/85... Total aside, but it's also more accurate to say that performance.now() is a monotonic clock rather than a counter. Counters don't necessarily have relationships with elapsed time, but performance.now() does, and it's conceptually the same as 'CLOCK_MONOTONIC'.