History: Stub out support for theming

[noisysocks]

Asana Task/Github Issue: https://app.asana.com/1/137249556945/project/1209121419454298/task/1211842297546424?focus=true

• Updates initialSetup and adds onThemeUpdate to allow setting a theme and themeVariant per https://app.asana.com/1/137249556945/project/1209121419454298/task/1212083006586484?focus=true.

• Adjusts the default background colour according to the set variant so that something observable happens when setting a theme.

• Marks customizer.defaultStyles as deprecated.

Intention here is to do the minimal amount needed to unblock the native apps. In follow up PRs I’ll import theme variables from the design-tokens repo and update more than just the background colour.

Testing Steps

1. Browse to https://deploy-preview-2066--content-scope-scripts.netlify.app/build/pages/history/.
2. Check that background colour is light grey (as before).
3. Switch theme to dark using System Settings panel or by setting ?theme=dark.
4. Check that background colour is dark grey (as before).
5. Browse to https://deploy-preview-2066--content-scope-scripts.netlify.app/build/pages/history/?themeVariant=rose. (Replace rose with any valid variant.)
6. Check that background colour is pink (or whatever).
7. Switch theme to dark using Customize panel or by setting ?theme=dark.
8. Check that background colour is purple (or whatever).

Checklist

Please tick all that apply:

• I have tested this change locally
• I have tested this change locally in all supported browsers
• This change will be visible to users
• I have added automated tests that cover this change
• I have ensured the change is gated by config
• This change was covered by a ship review
• This change was covered by a tech design
• Any dependent config has been merged

---

Note

Adds theming to History (theme and themeVariant) with live updates via onThemeUpdate, schema/type support, CSS variants, mocks, and integration tests.

• App/UI:
  • Use ThemeProvider and expose data-theme and data-theme-variant on the root layout in components/App.jsx.
• Provider:
  • Introduce global/Providers/ThemeProvider.js to derive theme from initial setup, system preference, or onThemeUpdate.
• Messaging & Types:
  • Extend initialSetup response with theme and themeVariant.
  • Add onThemeUpdate subscription; update generated types/history.ts and JSON schemas.
• Mocks:
  • Support URL overrides for theme/themeVariant and subscription delivery in mock-transport.js.
• Styles:
  • Add CSS for theme variants (e.g., coolGray, slateBlue, green, etc.) updating background variables in styles/history-theme.css.
• Integration Tests:
  • Add history-theme.spec.js and helpers to assert theme/variant and background color; include in Playwright config.
• Deprecation:
  • Mark and warn that customizer.defaultStyles is deprecated; use themeVariant instead.

^{Written by Cursor Bugbot for commit ca9c553. This will update automatically on new commits. Configure here.}

[netlify]

✅ Deploy Preview for content-scope-scripts ready!

Name	Link
🔨 Latest commit	ca9c553
🔍 Latest deploy log	https://app.netlify.com/projects/content-scope-scripts/deploys/6928e49a5e05a2000855dbac
😎 Deploy Preview	https://deploy-preview-2066--content-scope-scripts.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[github-actions]

Temporary Branch Update

The temporary branch has been updated with the latest changes. Below are the details:

• Branch Name: pr-releases/pr-2066
• Commit Hash: 6e10e2f548e99b3ed2874e20cab4ec535b9214fa
• Last Updated: November 27, 2025 at 11:54:36 PM UTC
• Install Command: npm i github:duckduckgo/content-scope-scripts#6e10e2f548e99b3ed2874e20cab4ec535b9214fa

Please use the above install command to update to the latest version.

[github-actions]

[Beta] Generated file diff

Time updated: Thu, 27 Nov 2025 23:55:03 GMT

Apple

    - apple/pages/history/dist/index.css

• apple/pages/history/dist/index.js

File has changed

Integration

    - integration/pages/history/dist/index.css

• integration/pages/history/dist/index.js

File has changed

Windows

    - windows/pages/history/dist/index.css

• windows/pages/history/dist/index.js

File has changed

[shakyShane]

@noisysocks screenshots failed, indicating you might have changed something that impacts the default/not-implemented case.

failing snapshots

[noisysocks]

@noisysocks screenshots failed, indicating you might have changed something that impacts the default/not-implemented case.

Love it when tests pick up an actual bug!