To download and install the PS Vita Font Package, which is typically required to fix missing or garbled text in games—especially when using the Vita3K emulator—you should download the official firmware files directly from Sony's servers. Direct Download Links
Manual Replacement (Advanced): You can manually replace system fonts by renaming .otf files to ltn0.pvf and placing them in sa0:data/font/pvf/ using an FTP client like VitaShell, though this is riskier than using an installer. Common Fixes for Errors
If you want to change the actual system fonts on your physical Vita, you don't need a firmware package; you need a font installer download font package psvita fix
Go to Settings → System → System Information. Write down your version (e.g., 3.65, 3.68, 3.74). You must match the font package to this number.
The PS Vita Font Package Fix: A Solution to Enhance User Experience To download and install the PS Vita Font
Since direct linking to copyrighted Sony files violates many TOS, here are the legitimate channels to find the hash-verified font package:
Select the font package file (PSP2UPDAT.PUP) you just downloaded. Write down your version (e
Language Support: Improving support for non-Latin characters (CJK characters) in fan-translated games. Prerequisites
The Result: The Vita falls back to a "fallback font" which only contains basic symbols, hence all letters become squares.