What mui/material-ui shipped
Written by FoxPlug from public releases; not affiliated with MUI. An automatic summary of the public release, pull request and commit data of github.com/mui/material-ui. MUI did not write it and does not use or endorse FoxPlug. Every line links to the public change it describes.
Week of September 21, 2026
What shipped
- AvatarGroup TypeScript performance improved by using typeof Avatar directly instead of React.ElementType, reducing type instantiation checks. Pull request #49213
- InputBase and other input components now render the theme.focusVisible ring, closing gaps in focus indicators across the library. Pull request #49152
- Material-nextjs fixed SSR style output to escape the style end tag, preventing user-controlled strings from closing the stylesheet element early. Pull request #49183
- Babel dependencies upgraded from 7.x to 8.x to match @mui/internal-code-infra requirements and avoid API version mismatches. Pull request #49162
- Modal aria-hidden attribute now correctly excludes non-portal modals, preventing them from being hidden from the accessibility tree. Pull request #49026
- Button fixed a style leak where loadingPosition: 'center' was applying to all buttons regardless of loading state. Pull request #49182
- BottomNavigationAction selected prop now properly declared in types and propTypes after being silently accepted. Pull request #49190
- Material utils and six component barrels converted to TypeScript with tsc-emitted declarations. Pull request #49185
- Lab package fully converted to TypeScript, eliminating all hand-written .js + .d.ts pairs in favor of single source files. Pull request #49140
- Documentation added warning about untrusted values in sx prop that can contain closing braces and inject arbitrary CSS. Pull request #49199
Why it matters
This week focused on performance improvements, security fixes, and TypeScript migration progress. The AvatarGroup type-checking fix and InputBase focus-visible additions address real developer pain points, while the SSR style escaping and Button style leak fixes resolve accessibility and rendering issues.
Changelog entry
- AvatarGroup: Reduced TypeScript instantiation checks in slotProps by using typeof Avatar directly Pull request #49213
- InputBase: Added theme.focusVisible ring rendering for input components Pull request #49152
- material-nextjs: Fixed SSR style output to escape closing style tags in values Pull request #49183
- core: Migrated Babel dependencies from 7.x to 8.x Pull request #49162
- Modal: Fixed aria-hidden to not apply on non-portal modals Pull request #49026
- Button: Fixed loadingPosition style leaking to non-loading buttons Pull request #49182
- BottomNavigationAction: Added selected prop to type definitions Pull request #49190
- ButtonBase: Fixed LazyRipple retaining event objects when ripples disabled Pull request #49000
- material: Converted utils and six component barrels to TypeScript Pull request #49185
- lab: Completed full TypeScript conversion with tsc-emitted declarations Pull request #49140
This week: AvatarGroup TS perf boost, InputBase focus indicators, SSR style tag escaping, Modal aria-hidden fix, Button style leak fix, and full Lab TypeScript migration.
Material-UI shipped several important fixes and improvements this week. AvatarGroup TypeScript performance improved significantly, InputBase and inputs now show focus indicators, SSR rendering is more secure with proper style tag escaping, modals no longer incorrectly hide from accessibility trees, and the entire Lab package completed its TypeScript migration. These changes enhance both developer experience and application quality.