v18.3.1
Improve DEV errors if string coercion throws (Temporal.*, Symbol, etc.) (#22064)
Improve hydration fixture, support older versions of React (#14118)
Minimally support iframes (nested browsing contexts) in selection event handling (#12037)
Hydration DOM Fixture (#13521)
Add <progress> to DOM fixtures (#18293)
Bump Prettier (#17811)
Default to first non-disabled option for select elements (#10456)
Update prettier to 1.8.1 (#10785)
Fix failing Prettier command (#10268)