About your thumb drives, small ones/older ones are generally formatted as FAT32 which is a universal basic hard drive format that really does go all the way back to DOS -- or if they were an advanced large capacity thumb drive they might be formatted as NTFS format which is the current Windows format.
Key thing is that thumb drives are always an attractive snack bit for a Windows virus.Leaving stuff on your Mint desktop, that's a folder on a hard drive that is formatted in Ext4, the current Linux standard high efficiency high security format. To get to your data on your desktop folder, a virus has to deal with a hardened Linux operating system and a drive format it generally wasn't even created to be able to read, much less to go screw up.
So, if you are going for maximum data security, only put stuff on your thumb drive when you need to archive copy it, the rest of the time your data is safer on your Linux desktop stuck inside your personal data folder.
Don't leave thumb drives plugged in all the time, they are at an ongoing risk of a Windows virus or worm or etc. etc. while they are just hanging out of the front of the machine. Really, it is about as safe as a strip of bacon sticking out of the wire mesh of a dog pen.
Very attractive. Gets eaten pretty quick.
Remember, Mint can read/write any hard drive format, and it generally matches the write format to what it finds on the write to device. You can reach inside your Windows NTFS format with Mint and read files, then write them to your Linux hard drive desktop -- the format of the data is changed during this copy/paste.
Read NTFS, write Ext4. And vice versa if the data is going the other way.
Now, when this doesn't happen flawlessly, it causes you a heart ache --
so keep your data on a folder on your desktop as its normal resting place, and only copy it over to your flash drive one way (periodically back it up). Only write it once (when recovering from a disaster). Keep the thumb drive safe in a drawer -- not plugged into something all the time.
So, what did we learn? Bouncing data files back and forth between hard drive formats isn't recommended as a repeated repeated repeated activity because "shite can always happen" if you give it enough chances to happen.
One of the drives involved being a little sour can do it to you, if you bounce stuff between drives and formats all the time.
..... that thumb drive has a limited read/write life-span too, did you know that? Flash drive "trim errors" do accumulate, cutting down on the drive's capacity.