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+# File Systems
+
+The app currently makes the following assumptions:
+
+- NTFS is used on Windows
+- APFS or HFS+ is used on macOS
+- EXT4 is used on GNU/Linux
+
+On those 3 platforms, using a file system with similar path restrictions, case
+and unicode normalization sensitivity as the assumed one(s) may work (e.g.
+using EXT3 on GNU/Linux should work although we don't officially support it).
+
+On other platforms, using a file system with similar path restrictions, case
+and unicode normalization sensitivity as EXT4 should work too (e.g. using EXT4
+on BSD should work too).
+
+Please note that all FAT versions are currently unsupported.
+
+In case you're successfully using another platform (e.g. some BSD flavor), or
+GNU/Linux with another file system than EXT4 (e.g. BTRFS or ZFS), your
+feedback is welcome!
+
+## File System / Platform Matrix
+
+| File System | Platform      | Status |
+| ----------- | ------------- | ------ |
+| APFS        | **macOS**     | **supported, actively tested** |
+| EXT3/EXT2   | GNU/Linux     | should work |
+| EXT4        | **GNU/Linux** | **supported, actively tested** |
+| FAT         |               | won't work |
+| HFS+        | **macOS**     | **supported, testing should be back soon** |
+| HFS+        | GNU/Linux     | won't work |
+| NTFS        | **Windows**   | **supported, actively tested** |
+| NTFS        | GNU/Linux     | won't work |
+| [Add your file system / platform][Edit] | | |
+
+[Edit]: https://github.com/cozy-labs/cozy-desktop/edit/master/doc/usage/file_systems.md