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Firefox ignoring system timezone

Felipe Silva
Felipe Silva
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Firefox 115.0b7 is not correctly handling my system timezone, and using GMT instead. This only happens in specific pages, such as when accessing a website, or in `about:home`. It doesn't happen in `about:config` or `about:profiles`, for instance.

`privacy.resistFingerprinting` is set to `false`. The problem persists in Troubleshoot mode. The issue isn't present in Firefox ESR 102.12.0.

Running `date -R` with the system shell: `Sat, 22 Jul 2023 12:10:42 -0300`

Javascript console at `about:config`: ``` > Date() "Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time)" > new Date() Date Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time) > (new Date()).getTimezoneOffset() 180 ```

Javascript console at `about:home` or `https://example.com`: ``` > Date() "Sat Jul 22 2023 15:10:42 GMT+0000 (GMT)" > new Date() Date Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time) > (new Date()).getTimezoneoffset() 0 ```

Firefox 115.0b7 is not correctly handling my system timezone, and using GMT instead. This only happens in specific pages, such as when accessing a website, or in `about:home`. It doesn't happen in `about:config` or `about:profiles`, for instance. `privacy.resistFingerprinting` is set to `false`. The problem persists in Troubleshoot mode. The issue isn't present in Firefox ESR 102.12.0. Running `date -R` with the system shell: `Sat, 22 Jul 2023 12:10:42 -0300` Javascript console at `about:config`: ``` > Date() "Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time)" > new Date() Date Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time) > (new Date()).getTimezoneOffset() 180 ``` Javascript console at `about:home` or `https://example.com`: ``` > Date() "Sat Jul 22 2023 15:10:42 GMT+0000 (GMT)" > new Date() Date Sat Jul 22 2023 12:10:42 GMT-0300 (Brasilia Standard Time) > (new Date()).getTimezoneoffset() 0 ```

Chosen solution

Apparently, this problem is exclusive to NixOS and is being tracked here.

Read this answer in context 👍 0

All Replies (5)

Paul
Paul
  • Top 25 Contributor
  • Moderator
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Hi

Instead of using a Beta version of Firefox, what happens when you use the current Release version?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Do you have enabled "Resist Fingerprinting" if you check this pref on the about:config page as that places you in the UTC timezone?

zeroknight
zeroknight
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Visit about:config, search for "fingerprint" and reset all bold modified settings to default.

Felipe Silva
Felipe Silva Question owner
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The issue also happens with Firefox 115.0.2 (latest release version). Resist Fingerprinting is disabled, and all fingerprint-related options are set to default.

Additionally, I'm using NixOS: nixpkgs is set to `nixos-unstable` (commit 12303c65), with package `firefox` (v115.0.2).

Felipe Silva
Felipe Silva Question owner
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Chosen Solution

Apparently, this problem is exclusive to NixOS and is being tracked here.