i made DynamicFont for tiny spaces (and everything else).
select TabContainer, in the inspector: Themes Overrides > Fonts and select Font to create a DynamicFont
in Font Data you can load the font.ttf you want.
also you can save the DynamicFont if need to use in other nodes.
search in YT or somewhere else if need more info or tutorials.
i would to post a photo of example but the page dont let me :/