[mircea]

From https://sites.google.com/site/udfintro/ :

> Although an implementation may use a journal to protect metadata integrity, this does not guarantee interoperability between platforms since it is not part of the standard.

it seems it's left up to the implementation.

[londons_explore]

Non-interoperability of a journal isn't a massive downside. It just means after a system failure, you need to plug it back into the same OS first.

Obviously that needs to be enforced with some kind of "do not mount" option so it isn't accidentally used on another OS.

[orbital-decay]

For USB drives, it means that if you take it out from your work PC in a hurry, it might not be usable on your home Mac. Pretty serious I would say.