I have a soldering iron which I thought of using but I must say I am not a good opperator and as the window is in situ and not lying flat I am not sure of my ability.
I did see those tab thingies that dave p suggests and have ordered them via the net to give it a try.
When I got my new hood fitted, one of the terminals broke off. The fitter used what sounds like dave p suggested and the demister has worked faultlessly since. This was about 4 yrs ago now so it’s obviously good stuff.