Keyboard Event Propagation Control

What: Keyboard event handlers can now stop event propagation to other handlers using event.stopImmediatePropagation().

How to use:

// For developers building on Claude Code's UI framework
useInput((input, key, event) => {
  if (input === 'q' && shouldQuit) {
    event.stopImmediatePropagation();  // Prevent other handlers from running
    handleQuit();
  }
});

Details:

• Third parameter added to keyboard event handlers containing the event object
• Enables priority-based event handling for modal dialogs, focus management, and vim-mode implementations
• Backward compatible - existing handlers with 2 parameters continue to work
• Implements DOM-style event propagation patterns
• Evidence: New VO1 event class at line 71066, B11 base class with stopImmediatePropagation() at line 69922, and updated callback signature in QT9() at line 71693 in pretty-v2.0.24.js