When downloading the Mozilla Firefox web browser from the official Mozilla website a unique identifier is included in the installer file which allows the company to trace the end user without their consent.
source: https://www.ghacks.net/2022/03/17/each-firefox-download-has-a-unique-identifier/
archived source: https://wellthissucks.xyz/2022/03/17/mozilla-telemetry-in-firefox-installer-archived-source/