I too grew up with Seafoam that my Mother and Grandmother made.
My Grandmother would go outside and ‘feel the air’ to make sure there wasn’t too much humidity that day.
They also made it with no ‘fancy’ thermometers, just the drop a ball of the bubbling mixture in a glass of water.
As a kid, I was shooed to the other side of the kitchen, when it was time to combine the bubbling hot ingredients.
The nuts were not ‘store bought’ but whatever my Dad and and I could go out in the woods and gather.
Their’s was far superior to what any store put out.