Different typefaces have different widths. A substitute typeface can make text spill out of text boxes or buttons.
(Generated for illustrative purposes) Publication Date: April 2026 Keywords: Font substitution, fallback font, text rendering, Unicode, missing glyph, typography, digital publishing Font substitution will occur continue
Understanding Font Substitution: Causes, Impact, and Solutions Different typefaces have different widths
Appendix B — Checklist for Designers/Developers digital publishing Understanding Font Substitution: Causes
This warning is your computer’s way of saying: "The person who made this file used a font that I don't have installed. I'm going to pick a different font that looks 'close enough' so you can still read the text."
7.2 Font Stacks and Fallback Planning