An Update in customer locale field doesn't trigger the update customer update mutation

[ErwinPlones]

If a customer changes from language in our shop, the locale field in the customer is updated, but this doesn't not trigger the customer update mutation. Is this a bug or should it not trigger the customer_update (webhook). and what is there a work around?

I need to updat a value in klaviyo when this value change.

kind regards 

Erwin