2. Perform Cache integrity check in Steam
It sounds weird, but this solution works... The root problem is in Windows firewall
Copy-Pasted text from Reddit
I fixed it. Here's what I did.
First of all, I went inside of \steamapps\common\Life is Feudal Your Own\art\fonts and tried to double click the font file. My computer said it wasn't a valid font file. According to my research this is caused by the firewall being off, turning it on corrects this issue. (Didn't fix it at first, but could play a hand in it.) After that, I deleted the fonts folder in \steamapps\common\Life is Feudal Your Own\art\fonts and the fonts folder in \steamapps\common\Life is Feudal Your Own\core\fonts...verify the intergrity of your steam cache, problem is solved. I now have text inside of the entire game!