Firefox

As an IT Engineer this concept frankly terrified me and feels like your opening yourself up to a potential zero click attack - such as https://threatpost.com/apple-mail-zero-click-security-vulnerability/165238/

So my initial answer is an emphatic "please do not the ZIP". It could be as mundane as a ZIP bomb, or it could explain a vulnerability in the operating system or automatic extraction program. Having a human required to open the ZIP prior to its expansion reduces its attack surface area somewhat (but not eliminates it) because it allows the human to go "huh this ZIP looks funny" if something is off, rather than just dispatching an automated task.

With that out of the way - what's your use case with this? There has to be a specific reason your interested in saving a few clips here on one highly specific archive format, but not others like the tar unix archive, 7z, or RAR.

That sounds like a great idea until you download a zip bomb

I think it needs to be done by the operating system, extensions nowadays don't have the permissions to do that.

When I was using MacOS it automatically extract zipped files and I hated it so much, you accidentally click on a link, it automatically saves in download and automatically unzip it, leading to too much trash in downloads...

You could write a bash script using inotifywait to watch for new files in your download folder and extract them if they are archives.

If this werent a firefox question id say wget url | tar -xvf