I think I found a typo in a playground of the documentation, more precisely about text input restriction.
The PG works anyway thanks to a crash (the first input that should restrict user to number input), intput instead of input line 40
Here it is : https://playground.babylonjs.com/#I1Y5YT#1
Ref in this tutorial/doc :
I came across similar typo (I think) by searching “intput” babylonjs out of curiosity.
Example : ArcRotateCameraGamepadInput | Babylon.js Documentation