If a FragmentContainerView contains only a ComposeView and is constrained to a toolbar with layout_height=0dp and layout_constraintHeight_min="60dp" , the ComposeView behaves like the toolbar is always 0dp, even though the actual size is 60dp. The ComposeView is still constrained to the toolbar, but its height will be +60dp and draw below the screen. The layout works fine if I add a height to the toolbar instead of using app:layout_constraintHeight_min.

See activity_main.xml

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