GParted is written to use the exfatprogs [1] package, not the exfat-utils [2] one. These packages have different command line options.
[1] https://github.com/exfatprogs/exfatprogs [2] https://github.com/relan/exfat See upstream report [3] and fix [4]. [3] https://gitlab.gnome.org/GNOME/gparted/-/issues/137 [4] https://gitlab.gnome.org/GNOME/gparted/-/merge_requests/66 This fix was included in GParted v1.3.0 released on May 3, 2021. Curtis Gedak
