If browsers have enough low-level access to my storage hardware to carry out timing attacks for fingerprinting, it seems likely they also have enough to maliciously chug the hardware sufficiently to degrade capacity over time and otherwise impact system integrity. I hate the thought of some random website writing and overwriting random bytes in a tight loop in the background while I'm browsing elsewhere to find the cause of my slow disk subsystem.

To that end an option to disable storage access by type would be nice to have. All I see in firefox settings is the ability to block all storage including cookies, and the ability to block persistent storage when the site requests it. It's not clear to me how the OPFS system in TFA relates to either of these, but I'd guess that it's a separate system. There's a bunch of storage quotas in about:config, but nothing obviously related to OPFS (that I can see).

Given the choice I would be happy to allow traditional cookie storage and block everything else with any exceptions I need (none that I can think of) on a per-site basis. If this can be achieved via about:config, I'm all ears!

While looking at my storage data, I see youtube has 174(!) cookies and 57M data stored on my machine. Sigh.