If an invalid stylesheet is applied to application Then for some strange reason QHeaderview text characters looks like it is chopped. 

Further there is an odd interaction with how QHeaderViews get their font set once they've been applied as a header view for a QTableView. 

The issue is more noticeable on macOS, but is also present on Windows

Attached example reproduces it.

Follow these steps to reproduce:
1. Extract and Build sample application with Qt 5.15.17
2. Launch the application.
3. Press push button "1. Create Group and Table View"
4. Notice the font of the header view
5. Press push button "2. Apply invalid style sheet"
6. Press push button "1. Create Group and Table View"
7. Notice the font in the second header view differs from the first