The term “cracker” has nothing remotely to do with slavery. See “Cracker, The cracker culture in Florida history”. The “crackers” (mostly too poor to own slaves anyway) were mainly of Scots-Irish origin.
The term most likely ha to do with whips they used when they were the Florida “cowboys” (this state used to have some of the biggest herds in the country).
It may also have to do with “cracking” corn, a reference to making moonshine, which was particularly prevalent along the Georgia-Florida border.
Don’t care what it says.
I dated a black girl for 7 years. I know what it means.