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Date.prototype.toJSON() and Date.prototype.toISOString() discrepancy

  • 6 பதிலளிப்புகள்
  • 0 இந்த பிரச்னைகள் உள்ளது
  • 58 views
  • Last reply by Mathias Frost

console.log(new Date().toJSON()); console.log(new Date().toISOString());

// Actual output: // 2023-05-27T04:21:13.004Z // 2023-05-27T06:21:13.005Z

// Expected output: // 2023-05-27T06:21:13.004Z // 2023-05-27T06:21:13.005Z

This happens only on Firefox and Firefox Developer Edition on one of my PCs and not the other. Firefox is version 113.0.2 (64-bit) and DE is 114.0b9 (64-bit)

Anyone experienced this before?

console.log(new Date().toJSON()); console.log(new Date().toISOString()); // Actual output: // 2023-05-27T04:21:13.004Z // 2023-05-27T06:21:13.005Z // Expected output: // 2023-05-27T06:21:13.004Z // 2023-05-27T06:21:13.005Z This happens only on Firefox and Firefox Developer Edition on '''one''' of my PCs and '''not''' the other. Firefox is version 113.0.2 (64-bit) and DE is 114.0b9 (64-bit) Anyone experienced this before?

தீர்வு தேர்ந்தெடுக்கப்பட்டது

Do you have enabled "Resist Fingerprinting" if you check this pref on the about:config page?

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All Replies (6)

தீர்வு தேர்ந்தெடுக்கப்பட்டது

Do you have enabled "Resist Fingerprinting" if you check this pref on the about:config page?

Setting `privacy.resistFingerprinting` to `true` fixed the discrepancy, but... why?

Note that best is to keep this pref set to false as this can cause issues.

I can't replicate this, with both RFP disabled and enabled I get the same UTC output as expected. Does it make a difference what timezone is set in the OS ?

Do you get the correct local time via console.log(new Date()) ?

Yeah, I noticed some undesirable side-effects from having that to true, but weirdly enough, when turning it back to false, the issue is still fixed:

console.log(new Date()) // Date Sun May 28 2023 18:49:13 GMT+0200 (Central European Summer Time)

console.log(new Date().toJSON()) // 2023-05-28T16:49:51.947Z

console.log(new Date().toISOString()) // 2023-05-28T16:50:10.427Z

Seconds diff is because I executed them individually.

End even werider (or not, depending on whether or not DE and normal Firefox share config), on Developer Edition, where I have not toggled privacy.resistFingerprinting, the issue is also fixed:

console.log(new Date()) // Date Sun May 28 2023 18:53:43 GMT+0200 (Central European Summer Time)

console.log(new Date().toJSON()) // 2023-05-28T16:53:54.024Z

console.log(new Date().toISOString()) // 2023-05-28T16:54:03.475Z

Not sure what to make of this :D Maybe some weird, edge-case bug...

Did you get the local time in the case where it went wrong ?

Yes, new Date() and new Date().toISOString() gave correct time