So Dropbox is no longer supporting anything besides ext4 on linux as of Nov 7th 2018. Here's how to work around that WITHOUT superuser permissions. First, create a sparse file of whatever size you'd like for your Dropbox folder. $ truncate -s 5G ~/.Dropbox.img Now we need to format this as ext4, But we want to make sure that we own the created file system, not the default of root. $ mkfs.ext4 -E root_owner=$(id -u $USER):$(id -g $USER) ~/.Dropbox.img Setup the loopback device with our EXT4 image $ udisksctl loop-setup -f ~/.Dropbox.img You may need to mount the device if it hasn't been already: $ udisksctl mount -b $CREATED_LOOP_DEVICE Check where our filesystem is mounted: $ mount | grep Dropbox.img Move any existing data from the previous dropbox folder to the new location: $ mv ~/Dropbox/{.,}* /$MOUNTPOINT/OF/DROPBOX/IMAGE/UUID$ Link our new folder back to the dropbox folder $ ln -s /$MOUNTPOINT/OF/DROPBOX/IMAGE/UUID$/ ~/Dropbox You can now star...