How control the autm. resizing of RadzenTabs in MAUI?

I have using the RadzenTab for input some properties of my application. But it not use the possible page size

When I smaller the size of the MAUI-App then it´s shrink correctly

How can i use the free space of the MAUI-App Container?

There is a problem unrelated to the tab - check the location of the About button. It is not right as well. This is the cause the tabs is not filling the whole space as well.