Gutenberg: Plugin Update to v9

[sirreal]

Call for Testing: p7DVsv-9jU-p2
Previous successful update: #45312

Process

• Install pre-release development versions for testing:
  • …
• Install and activate on edge sites RC (D49482-code, D49483-code)
• Publish a Call for Testing post (p7DVsv-9jU-p2)
• Draft public announcement and submit to Editorial for review
• Update to stable release (D49635-code)
• Activate v9.0 for all sites (D49484-code)
• Request update for Atomic sites (p9o2xV-132-p2)
• Publish internal announcements (p7DVsv-9lz-p2)
• Clean up unused releases
  • 8.7.1 (keep previous release)
  • …
• Update the Log of Update Attempts section in the FG and list patches applied (PCYsg-m14-p2)

To do

• Should be fixed: Image Block Does Not Appear Under Search Term "Image" When Adding a New Block #45136

Testing

• Manual testing
• Calypso E2E tests: Gutenberg: Trigger edge e2e tests #45622
• Teamcity tests

Known issues

• FB and IG block variations are hidden, should still be visible on wpcom (522-gh-wpcomsh and D49605-code)
• Several block patterns performance issue (waiting for: Inserter: Add block pattern category selection dropdown in main inserter WordPress/gutenberg#24954) (context: p1599556417407200-slack-C015AL3QL7M). Update: This has been merged and will be in 9.1

Blockers 🐛

Follow-up issues

• wpcomsh cleanup 500-gh-wpcomsh

[sirreal]

Prepping for 9.1: #45772