Add Qualification of Concept

[theorosendorf]

Is this what you're looking for to qualify the concept of font fingerprinting?

[svgeesus]

Font fingerprinting is mainly implemented through the JavaScript API of the browser. The main principle of this technology is that the browser can obtain and report the list of fonts available on the user's device. These font lists, combined with other browser and device information, can form a fairly unique browser fingerprint.

Here are some commonly used font fingerprinting techniques:

Font Enumeration: This is the most direct method. Just like checking which apps are installed on your device, websites can check which fonts are installed on your device. This is achieved through a function provided by the browser, which will return a list containing all installed fonts.

There are no details about this API but https://www.browserscan.net/ did indeed extract a list of 225 fonts installed on my device (incomplete, but it did find some unusual and thus identifiable fonts that I have installed).

A JS API is clearly faster than trying a list of fonts one by one.