LIPSTICK. A use for lipstick for mating surfaces.

[WmRMeyers]

Nothing new under the sun, is there? But can you still get carbon paper?

yep! https://www.amazon.com/s?k=carbon+pa...f=nb_sb_noss_1

There's usually some available at office supply stores here in the US, I'd expect stationers shops would still have some, too. It's gotten more expensive, though.

And I see Marv has already beat me to it!

Bill