Topic: the defaults for Firefox, General, Language & Appearance, Fonts

Change the fonts and colors websites use

Firefox - Wikipedia

Change browser language in Mozilla Firefox on Windows

How to Secure Your Firefox Browser

Firefox CSS

Mozilla Firefox 117 Will Introduce a Built-In, Automatic

Change website appearance settings in Firefox

Firefox 73 Enters Development with New Default Zoom Settings

How to Customize the Default Font in Firefox - GreenGeeks

Changing the Default Mozilla Thunderbird Message Font