What is this insulation goop?

I am repairing the Rosenberger plug on my Specialized Turbo - the power wires have been joined with what looks like a clear heat shrink tube and some goop that I can only imagine is to stop heat transmission and a bit of insulation. Anyone know what this is so I can replicate this? Is this what you call potting compound? I do want a reliable repair.
TIA for your wisdom.
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Could be dielectric grease? I was having problems with the connectors on the headlights on my wife's car. The cheap connectors and high current and heat was burning up the contacts, which I replaced twice. I added dielectric grease and no more problems. Maybe this is a similar application (although I've never seen it used that way)?

Dielectric grease is usually clear or slightly milky. No this. I'm guessing it's more of a silicone sealant to prevent water shorts...

Philaphlous said:

Dielectric grease is usually clear or slightly milky. No this. I'm guessing it's more of a silicone sealant to prevent water shorts...

Click to expand...

That makes sense. I saw the big wires and translated goop to being still runny/squishy, so thought dielectric because of the conductive properties; but ya, not clear like it would typically be.

Does remind me to add some to my phase and battery wire connectors though...

Up close it looks a bit like expanding polyurethane foam - the sort you use to fill gaps in your home to prevent draughts etc.