2018: Dropbox cuts off every Linux filesystem but unencrypted ext4

In August 2018, Linux users began receiving in-app warnings that Dropbox would stop syncing in November unless their Dropbox folder lived on an unencrypted ext4 filesystem. The change cut off widely-used filesystems including XFS (the Red Hat Enterprise Linux default), Btrfs, ZFS, and — pointedly — encrypted ext4 volumes, meaning users who had encrypted their disks for security were told to choose between encryption and Dropbox.

Dropbox justified the restriction by saying its client relies on extended attributes (xattrs) to track files, and that it would support 'the most common' filesystem to ensure a stable, consistent experience. Critics noted that several of the dropped filesystems do support xattrs, and that the move looked like cost-cutting on testing surface dressed up as a technical requirement. The backlash was loud across Linux communities, and third-party fixes appeared almost immediately.

Dropbox partially reversed course: by mid-2019 it restored sync support for ZFS, XFS, Btrfs, and eCryptFS on 64-bit systems. But the episode damaged trust with the Linux user base and became a textbook example of a platform unilaterally breaking working setups.