QuickDesigner: Settings: Unreadable spinner values on OSX

Steps to reproduce:

• start QC, go to 'Preferences'-> 'Qt Quick' -> 'Qt Quick Designer'
• check the line edits / spinner for 'Snapping' and 'Canvas' [see attached pic]

Current result:

• values are unreadable without resizing the Settings dialog

Expected result:

• no resizing necessary to use them