Question about Printing Out Paper (POP)

Did photographers years ago fix and wash this paper? Or, did they just Gold Tone it and wash? Or what general method was used to ensure a fairly stable final print?

I remember playing around with Kodak POP, and fixing resulted in considerable lightening of the image.

I understand more recent (last 50 years) use of the paper as a proofing medium..the impermanence of the image was desired..so the studio could sell conventional b/w prints.

Sometimes it was just washed, providing a proof print that would fade in a few weeks (seems like a good idea to me).

Sometimes it was fixed and gold toned, or gold toned and fixed, or even treated with a gold-toning fixer.

Fixing done properly doesn't bleach the image (much), it only changes the tones to a lighter brown. Gold toning darkens the tones again so the full range is more visible.

So what is the process one would follow to ensure stable/archival prints from POP that would not fade? Would it be expose, wash, gold-tone, rinse, fix and then a final wash?