"Topbar font" controls the font type for all the top bar fields.

To change the font for the top bar, click on the blue text to the right of the field "Topbar font" and choose the new font. 

"General font" controls the font type for 

• All headlines 
• Article text 
• Text in search field 

To change the font for the top bar, click on the blue text to the right of the field "General font" and choose the new font.