Change dashboard default theme to system for new users

[gtsiolis]

Problem to solve

The default dashboard theme currently is set to Light.

However, the dashboard supports syncing the theme with the dashboard, including workspace loading and login pages, using prefers-color-scheme.

This setting could be hard to discover and automatically using the system theme can improve UX for users that also prefer syncing system theme with light or time conditions. For example, see relevant macOS settings.

Proposal

Change dashboard default theme to system. 🌔

Things to consider:

1. There's no dark theme for gitpod-io/website.
2. There's no option to automatically sync editor theme. See also [dashboard] Sync theme preference between dashboard and editor #3982.
3. We only use local storage and do not persist theme selection for users.

[jankeromnes]

Proposal

Change dashboard default theme to system. 🌔

Yes 💯 💯 💯

I've wanted to do this for a while. @JanKoehnlein / @jldec cool to schedule?

[gtsiolis]

Taking a bias-for-action and scheduling this in groundwork. @jldec feel free to remove if needed. Cc @JanKoehnlein

/schedule

[jldec]

👍 to self-scheduling

[jankeromnes]

/assign