I opened up an article from the internet in Acrobat and made changes to it by highlighting and making notes but didn't save it. My computer died and then when I opened it again, I was unable to retrieve my document even though autosave has been enabled. I have looked in the temporary folder and the recycling bin but can't seem to find it.
Is there any way I can retrieve the document? I am using Mac by the way.
Your changes are very likely lost: when you open a file in the browser, but do not download it so that it gets saved on your computer, any changes made will be lost when you close that file - either by moving to a different web page, or by shutting down your browser - and that also applies to a crash of the browser or the computer.
Always download a document first, so that it is available locally, and then start to make changes. This way, the auto-save function can actually do it's job.