p-calendar Month Picker rejects text input

[Spiral1401]

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Plunkr Case (Bug Reports)
This behavior is visible on the demo page, for Month Picker:
https://primefaces.org/primeng/#/calendar

Current behavior
Using the keyboard to input or change the date ( mm/yyyy ) results in the field being cleared.

Expected behavior
Component accepts edits made by key input, similar to how the basic calendar works.

Minimal reproduction of the problem with instructions
Type 01/2018 in the box, click off or tab. Field clears. Use picker to select 02/2018. Change the 02 to 01, click off or tab. Field clears.

What is the motivation / use case for changing the behavior?
Ease/convenience of use