[meindnoch]

  >Temporal.Instant.fromEpochSeconds(0).toPlainDate()
  Uncaught TypeError: Temporal.Instant.fromEpochSeconds is not a function

Hmm, docs [1] say it should be fromEpochMilliseconds(0). Let's try with that!

  Temporal.Instant.fromEpochMilliseconds(0).toPlainDate()
  Uncaught TypeError: Temporal.Instant.fromEpochMilliseconds(...).toPlainDate is not a function

[1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

[zdragnar]

"The docs" also say that it's only available in firefox. If you're going to use the docs, you should use the docs.

[meindnoch]

This output is from Firefox :)