Column headers use wrong font on start

[blue42u]

To Reproduce

1. Change the default column font to something obviously different, like a cursive font. Apply and switch to the profile view. Note that the column headers have changed accordingly:
   

2. Close and re-open the database. Note that the column headers are no longer using the configured font:
   

Expected behavior
Column headers should always use the configured font.

Platform (please complete the following information):

• OS: Linux (Debian, GNOME 42)
• Architecture: x86_64
• Version: master (c3c7b63)

[blue42u]

Fixed by a7e0c10