Cookies were introduced to the web many, many years ago. Initially was deemed as a useful feature which allowed websites to remember certain things about you and your browsing activity so that in some instances, you wouldn’t need to start from scratch everytime you loaded that website.
However, while cookies are still useful, these days we’re seeing how companies are using these cookies to track your activity and use that data to serve up personalized ads, which can feel a bit invasive. The good news is that Mozilla has been working on trying to limit what cookies can do, and in Firefox 85, the company is clamping down on the use of what is known as supercookies.
Supercookies are essentially cookies, but are “hidden” which means that even if you clear your cache and browsing data, there is a chance that these supercookies will continue to remain. With Firefox 85, Mozilla will be clamping down on the use of the feature by isolating them. This is done by partitioning caches used by top-level sites, such as HTTP cache, image cache, favicon cache, HSTS cache, OCSP cache, style sheet cache, font cache, DNS cache, HTTP Authentication cache, Alt-Svc cache, and TLS certificate cache.
Ultimately, this feature should prevent supercookies from being abused, but not destroying their functionality altogether. If you value your privacy, then perhaps Firefox 85 might be worth checking out.