[core] Bump React to 18.3.1

[renovate]

Note: This PR was originally opened by Renovate bot, but we're expanding it to include all things needed to upgrade React and related dependencies to 18.3.1

Pending issues:

• ReactDOMTestUtils.act is deprecated in favor of React.act.
  • createMount ([test] Remove createMount test util #42703)
  • makeStyles ([test] Remove enzyme #42706)
• useAutocomplete: spread key warning ([base-ui] Fix React spread key warning in test #42744)
• Joy Autocomplete: spread key warning ([joy-ui][Autocomplete] Fix React spread key warning #42741)
  • Fix spread key warning in test ([joy-ui][Autocomplete] Fix spread key error in test #42775)
• makeStyles: findDOMNode is deprecated and will be removed in the next major release. ([test] Remove createMount test util #42703)
• withStyles: Support for defaultProps will be removed from function components in a future major release. Use JavaScript default parameters instead. ([styles][withStyles] Expect React defaultProps warning in test #42752)
• Fix type error in ReactVirtualizedTable.tsx demo (error) ([material-ui][docs] Fix type error in virtualized table demo #42757)
• Remove react-test-renderer ([core] Remove react-test-renderer #42784)
  • describeConformance
  • scripts/useReactVersion.mjs
• ReactDOM.render and ReactDOM.unmountComponentAtNode are deprecated ([mui-utils][test] Remove usages of deprecated react-dom APIs #42780)
  • elementAcceptingRef.test.tsx
  • elementTypeAcceptingRef.test.tsx
• mui-joy/Input.tsx proptypes issue (see CI log)
• Non-critical
  • react-simple-code-editor causes React to warn locally: Support for defaultProps will be removed from function components in a future major release. Use JavaScript default parameters instead.

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Original PR description

[](https://renovatebot.com)

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
react (source)	^18.2.0 -> ^18.3.1
react-dom (source)	^18.2.0 -> ^18.3.1
react-is (source)	^18.2.0 -> ^18.3.1
react-test-renderer (source)	^18.2.0 -> ^18.3.1

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Release Notes

facebook/react (react)

v18.3.1

Compare Source

v18.3.0

Compare Source

facebook/react (react-dom)

v18.3.1

Compare Source

v18.3.0

Compare Source

facebook/react (react-is)

v18.3.1

Compare Source

v18.3.0

Compare Source

facebook/react (react-test-renderer)

v18.3.1

Compare Source

v18.3.0

Compare Source

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[mui-bot]

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Generated by 🚫 dangerJS against af4699f

[DiegoAndai]

React 18.3 was released as a step towards upgrading to React 19. It is identical to React 18.2 but with warnings about the necessary steps to upgrade. These warnings are showing in this PR's tests. I'll be working on this same PR to try to fix the warnings to upgrade to 18.3 to pave the way for React 19.

[DiegoAndai]

Autocomplete warnings addressed in #42099

[aarongarciah]

@DiegoAndai this is now ready to review

[DiegoAndai]

Amazing! Two final things to update:

[DiegoAndai]

🚀