[ruibaby]

Problem

Preview documents run in an opaque origin (sandbox allow-scripts, no
allow-same-origin). Theme scripts that read localStorage, sessionStorage, or
document.cookie during startup throw SecurityError, which aborts theme hydration
(for example Astro islands in Ethereal) and breaks display settings, language
switching, and search widgets. Theme widgets that fetch /rss.xml also fail because
the preview connect-src allows only public APIs and the CORS filter covers only
theme and plugin assets.

Change

• Inject a small shim before any theme script in every HTML preview document: the
  Console page/revision preview routes and the sandboxed child used by token previews.
• The shim replaces only the blocked APIs with in-memory implementations:
  Storage-compatible localStorage/sessionStorage (including property access,
  length, key, and enumeration) and a per-document cookie jar. It does not expose
  real site storage or cookies.
• Leave the sandbox unchanged: no allow-same-origin, so preview scripts still cannot
  reach site storage, cookies, or the Console parent.
• Allow /rss.xml, /feed.xml, /sitemap.xml, and /feed/ in the preview
  connect-src and in the CORS filter so theme feed widgets work.
• Add tests for injection ordering, non-HTML and non-preview pass-through, CSP
  sources, and CORS coverage.

Validation

• bash gradlew test -x processUiResources passes.
• Verified the shim in headless Chrome under both an iframe sandbox="allow-scripts"
  and a real Content-Security-Policy: sandbox allow-scripts response:
  localStorage reads/writes, Object.keys, length, and document.cookie work.

Limitations

• Shimmed values live only for the current preview document. Refreshing resets them,
  and the administrator's real site preferences are not exposed to preview scripts.
• The POST candidate preview route is intentionally untouched; it renders into a
  script-free visual editing canvas.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	🔄 Running since 2026-10-26T08:42:19.395411Z	a090833	New commits

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: c68f872364

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

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[ruibaby]

@codex review

[ruibaby]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Another round soon, please!

Reviewed commit: 0be8bb9149

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".