I've seen this video and looked at the stuff on Amazon. Looks like an amazingly versatile bit of gloop for anyone that needs to bodge things from time to time. A bag of it is pretty cheap on Amazon as well. There are a few different brands, and some that come with pigments as well.
Moderator, Treatment Free Beekeepers group on Facebook.
https://www.facebook.com/groups/treatmentfreebeekeepers/
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