We followed the instructions, the glue fixed the tab back to the screen element surprisingly well, and the demister was fixed. For about 2 days. The tab is still stuck on, but the demister stopped working so I guess electrical conductivity was lost.
Intermotor 12919 Ignition Coil for ALDI / SEAT / SKODA / VW 1.2 1.4 1.6 1.8 2.0