[Vwdiesel] What is the candle wax GP extraction trick ?

[Smith, Michael]

I've been spraying WD-40 and every other day some penetrating oil, on my
stuck and dead GP, but someone offhandedly mention a "wax trick".
For some reason I am unable to search the archives from here at work. Web
geeks have site blocked or something.
Who can give me a real quick explanation of what that's about please?

Also, do you think that trying to extract said glowplug while engine is
still hot would help at all ?

Thanks

Mike in NB