The settings in the Duplicacy Web allow changing the temporary directory. However, the same directory also contains configuration files and scripts for the backups.
I would like do automatic ZFS snapshots of the backup preferences but leave temporary files out of the snapshots because they can be quite large in some cases. If the config and cache were in their own ZFS datasets, I could setup different snapshot policies for both. Currently, I have the temporary directory on a ZFS dataset with snapshots disabled so that old temp files don’t use any storage.