Add MEGA S4 (and other few questions, please) #6085

Add Mega S4 please
Mega doesn't support metadata headers like for example the one used to act as mtime.
So I think it's a perfect use case for JuiceFS: it's cheap (the cheapest), it has good redundancy etc.
But I've read that it doesn't support certain metadata and/or s3 headers stuff, so I think using something like JuiceFS to separate metadata from the data would be useful

Does JuiceFS requires any headers or metadata functionality to work with S3 object storage? Because mega is s3 compatible but has some missing things for example the mtime doesn't get saved (X-Amz-Meta-Mtime this one)

And I think maybe it has also other headers that are not supported (sorry I'm not much knowledgeable about s3 storage)
But the data can be seen/used using something like rclone configured as a s3 compatible remote.. but as I said it doesn't support X-Amz-meta-Mtime so I cannot use rclone (I need to keep the mtime).

Also, I was searching for something that could handle file locks (avoid race conditions), and in general save all the metadata, be faster (rclone metadata cache is not good because it isn't persistent but stays only in RAM, and if I scroll Finder gets stuck because it starts loading all the files etc, also in general I need something fast because I basically want to have Mega S4 acting as a "storage expansion" to my laptops, server and Android smartphones. But so that it can be usable, like without losing edits if two people are editing the same file or things like that.

I just want to be able to trust the storage to act as a real filesystem which I'm used to, without "not knowing" that I will lose this or that property, and without being painfully slow or having race conditions and conflicts etc

And I also need client-side encryption so that I know I will be the only one to see the data

I want it to act as a filesystem , and from what I understood, JuiceFS serves this purpose, right?
Can JuiceFS be a solution for me?

Is Mega S4 already usable?
Also, is there anyway to use JuiceFS on android?
Thanks