Cannot change property values for custom button in property view

Steps to reproduce:

• Create general empty project
• Create new Custom button (File -> new file -> Qt Quick Controls -> Custom Button)
• Drag and drop created button to Navigator in screen01.ui.qml file
• Size of the button seems to be wrong (1920x1080)
• Try changing the position, size etc of the button using property view
• -> changes seem to take no effect
• Did not see this with other controls I tried (dial, checkbox, slider. did not try every one of those)