What is the default value for inputFormat ?

[nichita-pasecinic]

What is the default value for inputFormat ?

does the adapter use the locale ?

[LukasTy]

We do not control its value explicitly.
By default it is taken from keyboardDate (for DatePicker component) field from the adapter.
dayjs example

[nichita-pasecinic]

What L stands for at dayjs ?
I assume is localized by default in dayjs ?

[LukasTy]

What L stands for at dayjs ?

Yes, it is localized date format—it depends on the selected locale.