Came across this and just ordered some. It’s called Sugru. It’s moldable silicon putty for DIYers. Comes in little foil pouches, which you open, then warm the silicon in your hands, and then mold it onto whatever you need. I ordered some for my titanium mugs to put a lip guard on them. After you put on the putty, it cures in 24 hours, and is heat proof and durable and all the yadda yadda that silicon is.
Edit: forgot to mention that with shipping to the US, it’s about $11

