BUG: TypeError: Cannot read properties of undefined (reading 'toLowerCase') in keyboard handler

GrapesJS version

• I confirm to use the latest version of GrapesJS

What browser are you using?

All browsers (Chrome, Safari, Firefox, Edge)

Reproducible demo link

https://jsfiddle.net/saeedhbi/tdsLa6qe/

Describe the bug

How to reproduce the bug?

1. Create a basic GrapeJS editor (version 0.22.11 or 0.22.14)
2. Add an input field component to the canvas
3. Focus the input field
4. Dispatch a KeyboardEvent where event.key is undefined for IME composition events (mostly in Chinese/Japanese/Korean keyboards)
5. Observe TypeError: Cannot read properties of undefined (reading 'toLowerCase') in console

What is the expected behavior? The keyboard handler should gracefully handle cases where event.key is undefined and either:

1. Skip processing for undefined keys, or
2. Use a default/fallback value, or
3. Check for event.key validity before calling .toLowerCase()

No error should be thrown, and keyboard functionality should continue working normally.

What is the current behavior? GrapeJS throws a TypeError when keyboard events originate from input fields and the event.key property is undefined. The internal keyboard handler calls event.key.toLowerCase() without null/undefined checks, causing the application to crash.

Error message:

TypeError: Cannot read properties of undefined (reading 'toLowerCase')

Code of Conduct

• I agree to follow this project's Code of Conduct