I've enabled "Delete cookies and site data when Firefox is closed" but while all cookies gets deleted, some random site data does not. Are my settings wrong, is this a bug, and what even is that data?
Additional Info: I use RFP, want to keep browsing history and site settings. Thank you very much.
That could simply be the cookies.txt file with no content whatsoever.
Firefox stores cookies in a DB file called cookies.sqlite, i just cleared cookies on a fresh new Firefox profile and the file is 524.3kB. A text dump of the file has four lines of text that describe the structure of the cookie database and that's it. No actual content.
Sounds like it's localStorage. But I'd expect that to be covered by "site data" in that option.
It's a bit like cookies, but just for one site. Some think they can avoid cookie consent banners with localStorage.
Firefox has a page on the topic.
What is the data it's keeping? 25-100 bytes doesn't seem like there's anything actually there.
8 bytes is enough to store 18,446,744,073,709,551,616 (18 quintillion) different values, more than enough space for a fingerprint ID. The size of the data shouldn't factor into the potential threat.
Oh for sure, I just wonder if the size being the same on 2 of them is a result of Firefox storing some default data there on cleanup by accident.
Oh, I get it now! In my sleep deprived state I missed that two of them had the same size. That seems like a reasonable guess, I'm just paranoid about cookies :P
Except the actual content is very likely boilerplate stuff.
My point still stands. The size of data says nothing about its contents. If OP is concerned about this from a security or privacy perspective, you shouldn't be writing them off because it's only 100 bytes.
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