Problem in high-density header with flyout

Hi.

I have two forms . One form has high-density header that includes webresorce . And I see chevron   in the header of form. All right.

In the second form - same header with selected option to show header flyout . The header includes same webresource. I doesn't see a chevron on the form and not see this in Power App. What the problem ?

There are twi different forms of incident 

any idea ?