Personas 20 Question: How to switch the top line of a tab strip card to "not visible"

Hello all,

We have installed SAP Screen Personas 20 ( SP 02) for a customer and most application run fine.

We can Switch  tabstip cards to "not" visiible 

We want to disable all tabstrip cards except one.

But we can not switch the   top line with the text field of the one remaining  tabstrip card to White Color or to " not visible".

We can delete the text of the top element, but the rest of the tab Strip Card top is remaining in the Standard SAP Color.

Example:

Using Transaction Va03  we disabled all tabstrips except "Item Overview" .

We can Change the Color of the border line, but we are not able to disable  or to change Color of the tab strip top text field as you see  it in the attachment..

If i click in this area i do not find any property  to change or disable this area.

Can somebody help us ?

Thanks in advance and Best regards

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