[dashboard] Change default color theme from Light → System

[jankeromnes]

Description

Until today, the default color theme in the dashboard was Light (regardless of your system preference).

However, changing the default to System makes more sense: This will cause Gitpod's theme to remain light, except if you've told your OS that all apps should be dark (in which case Gitpod will now honor that preference by default).

Related Issue(s)

Fixes #6395

How to test

1. Open the preview environment (the login screen should already match your OS preference for light or dark)
2. https://jx-default-system-theme.staging.gitpod-dev.com/preferences should have "System" theme pre-selected
3. If you change your OS color theme preference, the preview theme should automatically respond (without even needing a refresh)

Release Notes

[dashboard] Change default color theme from Light → System

Documentation

/uncc

[AlexTugarev]

/lgtm

works as advertised, but only for firefox on mac. tried with safari & chrome, but theme changes of the OS were not reflected.

[roboquat]

LGTM label has been added.

Git tree hash: 610ebcbd85ebce4292bede5023a6f160d71ef3d1

[roboquat]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: AlexTugarev

Associated issue: #6395

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• components/dashboard/OWNERS [AlexTugarev]

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[gtsiolis]

Whoa, it's happening! Thanks @jankeromnes @AlexTugarev! 🌔

[jankeromnes]

Many thanks @AlexTugarev! 🚀

but only for firefox on mac. tried with safari & chrome, but theme changes of the OS were not reflected.

Oh oh, forgot to test with Chrome / Safari 😬 will check and possibly open a follow-up issue. Thanks for catching!

[gtsiolis]

FWIW, I could be missing something but seems to work as expected on Chrome, Firefox, and Safari on staging. 🤷
Cc @jankeromnes @AlexTugarev