I agree with the coments made above: BTRFS is a perfectly reasonable choice for a GNU/Linux system, that many of us use for various reasons. If, going forward, the choice is between Dropbox and BTRFS, then I for one will not be re-formatting my systems.
The going has been good, and I have been very satisfied so far with the service. Kudos! But this just may be the time to seek alternatives (probably Owncloud in my case).
I *am* using ext4 (with encryption for my home mount) and it still gives that message. How do I tell which machine is causing the problem?
I'm running LUKS/ecryptfs on top of ext4 as is mandated by a corporate security policy for portable devices - which I have been using for many years.
This has gotta be a fairly common setup but is no longer supported ???
Yeah I think that's my setup too, isn't it a Ubuntu installation default??
I am using ext4 partition for my home folder, which is encrypted by default in Ubuntu, and still get this message. Does dropbox as a company wants me to move my sync folder to unencrypted space to compromise security of my data? Is this for real? Very disappointing.
I do use Ext4, yet received this message. What the hell?
EDIT: like commenter above, I use encrypted Ext4 (ecryptfs home folder on one machine, the more recent thing on others). You should support that and I will quit Dropbox if you don't.
Adding my voice to the chorus here - this is unacceptable to me. I'm on XFS (which btw, is the default on RHEL and derivatives and fully supports xattrs). I've been a Dropbox user since 2008 and this is the first major issue I've had with it... but I will absolutely stop using the service if it doesn't support common, modern and supported filesystems for some arbitrary reason that makes no technical sense.
I do share the average opinion here.
Please, Dropbox, change your mind.
I think that is just a bug. ecryptfs on top of Ext4 is still a full Ext4 with attributes. I hope they will reply to this.
Solved! : See answer