Hey, maybe it's Nostoc?
Nostoc: A green, jelly-like substance growing in lawns | MSU Extension
https://msue.anr.msu.edu/news/nostoc_a_g ... g_in_lawns
Within the category of “What is it?” lives a strange-looking organism called Nostoc. During summer 2014, several people brought in samples of a green jelly-like substance growing in their lawns. After a bit of digging, I identified the stuff as Nostoc sp., a genus of cyanobacterium formerly classified as blue-green algae. Nostoc has many colorful names including witches’ butter, mare’s eggs and meadow ears, among others.
It looks like specifically Nostoc pruniforme -- the ones also called "Mare's eggs"
...which led me to this -- I knew I had seen that term before
The Mare's Egg by Carole Spray The Mare's Egg
by Carole Spray