Big Sur/Mail Sidebar text size?

[Xairbusdriver]

Anyone know how to increase the text size (especially the 'un-read' messages text) or maybe even change the font in Mail.app (Big Sur macOS 11.4)?!

There is a setting in System Prefs/General:"Sidebar icon size" (Large/Medium/Small) which indirectly changes the font/text size of the mailbox label. However, it does not change the size of the number indicating un-read messages in that mailbox. That info remains in what appears to be a ~7 or 8 pt. text. It is also surrounded by an extremely light-grey circle that further reduces the contrast between the number and the white background.

I have attempted to use System Prefs/Accessibility/Display/Display tab:Increase Contrast checkbox. No perceivable help with contrast. I suppose "Spoken Content" might help...

[jchuzi]

Forget System Preferences. Go to Mail > Preferences > Fonts & Colors. You should be able to do it from there, but maybe not. I tried it for the sidebar but was not successful. Oh well...