Web Chat is not loading with error Uncaught TypeError: Super constructor null of anonymous class is not a constructor
- A bug in webpack@>=5.84.1 is causing the issue. Please update to webpack@>=5.90.0

Breaking changes

useSendMessage hook is updated to support sending attachments with a message. To reduce complexity, the useSendFiles hook is being deprecated. The hook will be removed on or after 2026-04-03
styleOptions.uploadThumbnailHeight and styleOptions.uploadThumbnailWidth must be a number of pixels
useSuggestedActions type is updated to align with its actual implementation, by @OEvgeny, in PR #5122
Removed deprecated code: connect*, useRenderActivity, useRenderActivityStatus, useRenderAvatar, in PR #5148, by @compulim
Added named exports in both CommonJS and ES Modules module format, in PR #5148, by @compulim
Removed deprecated useFocusSendBox() hook, please use useFocus('sendBox') instead, in PR #5150, by @OEvgeny
HTML-in-Markdown is now supported. To disable this feature, set styleOptions.markdownRenderHTML to false

Added

Resolves #5083. Added sendAttachmentOn style option to send attachments and text in a single activity, by @ms-jb and @compulim, in PR #5123
- useSendMessage hook is updated to support sending attachments with a message
- useSendBoxAttachments hook is added to get/set attachments in the send box
Resolves #5081. Added uploadAccept and uploadMultiple style options, by @ms-jb, in PR #5048
Added sendBoxMiddleware and sendBoxToolbarMiddleware, by @compulim, in PR #5120
(Experimental) Added botframework-webchat-fluent-theme package for applying Fluent UI theme to Web Chat, by @compulim and @OEvgeny
- Initial commit, in PR #5120
- Inherits Fluent CSS palette if available, in PR #5122
- New send box with Fluent look-and-feel, in PR #5122
  - styleOptions.maxMessageLength to specify maximum length of the outgoing message
- Drag-and-drop file support, in PR #5122
- Added telephone keypad (DTMF keypad), in PR #5122
- Fixed botframework-webchat-fluent-theme/package.json to export *.d.[m]ts and default exports, in PR #5131
- Added support of styleOptions.hideUploadButton, in PR #5132
- Added styleOptions.hideTelephoneKeypadButton and default to true, in PR #5132
- Fit-and-finish on suggested actions and telephone keypad, in PR #5132
- Fixed to keep telephone keypad on-screen on click, in PR #5132
- Disabled send button and hid message length when telephone keypad is shown, in PR #5136
- Added dark theme support, in PR #5138
- Added an information message to the telephone keypad, in PR #5140
- Added animation to focus indicator and pixel-perfected, in PR #5143
- Integrated focus management for send box, in PR #5150, by @OEvgeny
- Added keyboard navigation support into suggested actions, in PR #5154, by @OEvgeny
- Fixes #5166. Fixed "attach file" button in iOS Safari should looks the same as on other platforms, in PR #5167, by @compulim
(Experimental) Added <LocalizeString /> component which can be used to localize strings, by @OEvgeny in PR #5140
Added <ThemeProvider> component to apply theme pack to Web Chat, by @compulim, in PR #5120
Added useMakeThumbnail hook option to create a thumbnail from the file given, by @compulim, in PR #5123 and #5122
Added moduleFormat and transpiler build info to <meta> tag, in PR #5148, by @compulim
Added support of rendering HTML-in-Markdown, in PR #5161 and PR #5164, by @compulim, @beyackle2, and @OEvgeny
Resolves #5184. Added channelData.webChat.styleOptions.typingIndicatorDuration to override the default typing indicator duration on a per-activity basis, by @compulim, in PR #5141
Resolves #4876 and #4939. Added support of livestreaming, by @compulim, in PR #5141

Fixed

Fixes #5050. Fixed focus should not blur briefly after tapping on a suggested action, by @compulim, in PR #5097
Fixes #5111. Fixed keyboard help screen to use HTML description list, by @compulim, in PR #5116
Fixes #5080. Fixed dateToLocaleISOString for handling sub-hour, by @marclundgren, in PR #5114
Fixes #5146. Fixed chat history focus indicator should not show up on tap, by @OEvgeny, in PR #5145
Fixes type portability issues by exporting types from all exported code, in PR #5148, by @compulim
Fixes missing exports of useNotifications, in PR #5148, by @compulim
Fixes suggested actions keyboard navigation skips actions after suggested actions got updated, in PR #5150, by @OEvgeny
Fixes #5155. Fixed "Super constructor null of anonymous class is not a constructor" error in CDN bundle by bumping to webpack@5.91.0, in PR #5156, by @compulim