Moving a WebEngineView from one screen to another seems to cause some confusion with select element geometry.
On the screen window is first displayed: expanding the select drop down list works as expected and the drop down will be positioned right below the select element.
On another screen: After having moved WebEngineView to another screen and clicking on the select element to expand the drop down will now cause the drop down to appear notably separated from the rest of the element and it's dimensions appear small in comparison. At worst the drop down may appear entirely outside the application window.

This issue appears only if high dpi scaling is enabled.

Steps to reproduce the issue:

1. Build & Run the attached project
2. Drag and drop the attached sample html (drop-down.html) to the app window to load it
3. After html is loaded move webengineview to another screen
4. Click on the select element & observe the dropdown position

For reference see the attached images.