Block web fonts with my new Safari content blocker StopTheFonts

April 3, 2023
By Jeff Johnson of Underpass App Company

A web font is a font that a web site loads from the web rather than from the installed fonts on your device. Google fonts with URLs that start with are examples of web fonts. Here's a web font named Amadeus:

Block me, Amadeus!

A few months ago I was looking for a Safari content blocker that could easily block web fonts, but for some reason I couldn't find one. If you know me, the solution was obvious: I had to make my own! Today I'm introducing StopTheFonts, a Safari content blocker for web fonts on iOS and macOS, available now in the App Store.

You can set StopTheFonts to block all web fonts by default or to allow all web fonts by default. For the simplest usage of StopTheFonts, just block everything. For more advanced usage, you can create rules for specific URLs. There are two rule types: web font rules and web site rules. A web font rule allows or blocks a specific font URL on every web site, whereas a web site rule allows or blocks all web fonts on a specific site URL. Regex is available as an option for URLs.

There are a number of reasons to use StopTheFonts: to protect your privacy, because every web font is loaded over the web, exposing your IP address and possibly other information, often to third parties; to make web pages load faster, because they don't have to wait for the fonts to load; to save bandwidth on carrier-limited connections. My personal inspiration for StopTheFonts was the font replacement feature of my extension StopTheMadness.

StopTheMadness can replace the fonts selected by the web page's style with your own selected fonts. Suppose that you want to customize which fonts are displayed on all web sites you visit in Safari. StopTheMadness font replacement rules automatically generate CSS @font-face rules, and every such rule requires a @font-family name. You can make StopTheMadness font replacement rules for the built-in fonts, which are limited in number, but the problem is that web fonts can have any arbitrary name. Your rules can't cover every possible web font. But what if you could block every web font? Then your StopTheMadness font replacement rules would only have to deal with the limited number of built-in fonts. StopTheFonts makes it easier to create a "blank slate" for font replacement rules in StopTheMadness.

By the way, the StopTheFonts app icon was designed by Matthew Skiles, who also designed the new app icons for Link Unshortener and Homecoming for Mastodon. Thank you once again, Matthew!

Get StopTheFonts now in the App Store.