Material Instance is missing in Content Browser in UE 4.25.2

Dear All ,
In the predefined materials in starter content, if I want to make the instance of existing material say Clay_Brick Material for scaling purposes, right click on it and if I choose to Material Instance at the top of pop - up window then material name labling appears and immediately after pressing Enter created material instance disappears in Content Browser, as a result corresponding material instance is not created.

What could be the solution of this discrepancy?

You have a filter set on the content browser:

308243-mat.jpg