Stage 4

• committee approval
• implement in two stable browsers/engines
  • polyfills
    • https://www.npmjs.com/package/string.prototype.matchall
    • babel-polyfill via core-js
  • webkit nightly
    • Safari TP
    • Safari stable
  • spidermonkey
    • firefox 66 nightly bug
    • firefox 67 unflagged
  • chakra
  • v8
    • chrome flagged issue
    • chrome unflagged (v74)
• significant in-the-field experience
• ecma262 PR approved
• prepare ecma262 (PR)
• merge test262 tests
• write test262 tests (PR)
• resolve final IsRegExp question issue

Stage 3

• committee approval
• spec editor signoff
• spec reviewer signoff

Stage 2

• receive developer feedback
• committee approval
• spec text written
• spec reviewers selected