Inside the ViewportToolBar, the "Click to Expand" ComboButton works incorrectly with Display Scaling

When Display Scaling is applied (e.g., 125%) and the Level Viewport is resized, the ComboButton in the SViewportToolBar does not behave as expected.

Normally, the ComboButton hides when there is insufficient space in the viewport.

However, with Display Scaling applied, the ComboButton gets hidden prematurely, even when there is still available space in the toolbar.

1- Set Display Scaling to 125% (or another non-default value).
2- Open Unreal Engine Editor.
3- Resize the Level Viewport, making it smaller.
4- Observe the ComboButton in the top-right corner of the toolbar: Initially, it hides certain buttons as expected.
As you continue resizing, the ComboButton disappears too early, despite available space remaining in the toolbar.