I got a separate flash drive for GParted, a Celeron.
I installed GParted on the Numbat PC to look at the flash drive and kind of see how GParted worked. (Although I think I might also have installed it on the Fossa PC at some point.)
sudo apt update
sudo apt install gparted
It looks like it calls the flash drive “General UDisk” and its partition table is msdos.
The Numbat’s SSD’s partition table is gpt and it has:
/dev/sda1 fat32 /boot/efi
1.05 GiB; 8.26 MiB used, 1.04 GiB unused; flags: boot, esp
/dev/sda2 ext4 /
237.42 GiB; 18.46 GiB used, 218.96 GiB unused
unallocated 1.34 MiB