COVID-19 and leg cramps.....

Cinchona bark.

During the summer months I tried all of the usual stuff.
Nanners,
Potassium,
More Gatorade than Coach Saban has ever had poured on him.
I usually stay away from bananas because they're so high in sugar, but my daily(ish) multivitamins supplement the shortfall.

Now...thanks to the vid, there's an ample supply of the stuff and lots of people like me keep a bottle in supply for days when I'm unusually steppy. I'll take a capsule before bedtime whenever I'm unusually active on a hot day or walk more than about 10,000 steps on a normal day.
I can't remember the last time I've been "struck by lightning" in the middle of the night but it seldom happens anymore.

MY mileage.
Yours will vary.