[lebdavis]

Summary

Keeps WebSocket collaboration working when Gutenberg stops exposing wp.sync, while retaining support for existing Gutenberg versions. Bumps the plugin to 0.5.15 so merging this PR to main triggers the standard GitHub Release workflow.

Uses VIP's shared-Yjs shim approach. Our legacy fallback is resolved when the provider is created, which also supports the global becoming available after bundle loading. No Worker deployment is needed.

Related: Automattic/vip-real-time-collaboration#226
Related: WordPress/gutenberg#81999

Validation

• 64 plugin tests passed, including production-bundle tests for provider-supplied Yjs, legacy fallback, precedence, late initialization, collections, missing Yjs, real sync messages, and no duplicate Yjs implementation.
• 19 release/workflow tests passed; release detection selects wp-collab-cf-v0.5.15 from the 0.5.14 baseline.
• PHP lint and contracts, production build, targeted JavaScript lint, and production dependency audit passed (zero vulnerabilities).
• Artifact checks passed for reproducible ZIP contents, version metadata, allowlist, and checksum verification.
• Compatibility code review completed with no actionable findings; the version-only follow-up is covered by release checks.

Post-Deploy Monitoring & Validation

The owner is currently the only consumer and has elected to test in the browser after release. Full two-editor testing against the Gutenberg PR build has not been performed.

On first installation of 0.5.15, the owner will check bidirectional editing, presence, undo/redo, save/reload, and reconnect. Expected signals are synchronized content and normal connection recovery; check the console for WP Collab CF: no Yjs module available or repeated connection/sync errors. If editing fails to synchronize, restore the previous working plugin/Gutenberg combination.

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