Title text:
Some surfaces may seem difficult to glue. But if you research the materials, find tables of what adhesives work on them, and prepare your surfaces carefully, you can fail to glue them in a fun NEW way that fills your house with dangerous vapors.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3194/
My first thought without looking anything up was that it was resin and hardener already mixed - cured epoxy.