Add Gmail compose domain skill

[guglielmofonda]

Adds domain-skills/gmail/compose.md covering field-tested compose mechanics:

• /mail/u/<email>/ account routing for multi-account sessions (+ transient "Temporary Error" on first load)
• Stable selectors: [gh="cm"] compose button, To/Subject/Body fields
• Minimized-compose state detection (offsetParent null) and restore
• Trap: Gmail's require-trusted-types-for CSP blocks insertHTML/innerHTML — documented the trustedTypes.createPolicy bypass (policy names are unrestricted) plus the InputEvent dispatch required for autosave to register the change
• Draft save/close/verify patterns

🤖 Generated with Claude Code

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Summary by cubic

Adds a new Gmail compose domain skill documenting a stable, end-to-end flow for opening, filling, and saving drafts, including a Trusted Types-safe HTML insert. This reduces flakiness by using robust selectors and covers autosave nuances.

• New Features
  • Multi-account routing via /mail/u// with note on transient “Temporary Error” on first load.
  • Stable selectors for Compose button and To/Subject/Body fields.
  • Detection and restore of minimized compose windows before filling.
  • Trusted Types CSP workaround using trustedTypes.createPolicy and InputEvent dispatch so autosave registers content.
  • Draft save/close patterns and verification via list row snippets.

^{Written for commit 575b711. Summary will update on new commits.}

[browser-harness-review]

✅ Skill review passed

Reviewed 1 file(s) — no findings.

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Put Gmail skill where goto_url can discover it

When agents follow this documented Gmail URL, goto_url() will not surface the new skill: helpers.py:52 maps a hostname to domain-skills/<first-label> after stripping only www, so https://mail.google.com/... looks under domain-skills/mail, not domain-skills/gmail. In the normal navigation flow the returned domain_skills hint is therefore missing for Gmail, so this compose guidance is easy to miss unless the agent manually searches the repo; move it to the directory the loader uses or update the loader to alias mail.google.com to gmail.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Scope body lookup to the active compose window

If Gmail already has another compose or reply editor open, this querySelector grabs the first message body in the document rather than the compose window opened for the current draft. Gmail supports multiple compose windows/minimized drafts, so following this snippet can overwrite and autosave the wrong draft; scope the lookup to the visible compose dialog/container you just opened before assigning innerHTML.

Useful? React with 👍 / 👎.