Be sure to block JavaScript as well. Makes the web a lot faster, and very often better too, with only the occasional site (though considerably more of certain types of sites) breaking. What I settled on a couple of years back was to disable JavaScript with uMatrix, but have that extension disabled in Private Browsing mode, so I can just open a Private Browsing window if I want to run something with JS.

In Firefox, you also just have the “Allow pages to choose their own fonts, instead of your selections above” checkbox in Settings → Fonts → Advanced that you can untick, which will stop most web fonts from loading, though Private Use Area code points (used in icon fonts) will still work from web fonts (so that Google’s Material Icons with its stupid ligation technique is just about the only thing that will be mangled).

It can be done in Firefox, it is just one setting in about:config.

gfx.downloadable_fonts.enabled

Some sites rely on icon fonts for buttons, and they appear as Unicode placeholders instead. I don't mind, and consider it a time-saving benefit which reduces my effort spent on low-quality websites.

uBlock Origin can: https://github.com/gorhill/uBlock/wiki/Per-site-switches#no-...

In Chrome, uBlock origin can block webfonts.

Some adblockers can do this.