I found this video on youtube: https://www.youtube.com/watch?v=gikVjBnpTRQ

It looks like it is from a company Google purchased, and now they don't plan to move forward with it.

I don't have Photoshop and won't ever. Can it be used with Gimp somehow?

There is a plugin shellout.py that will load these. AFAIK it is already incorporated into Partha Gimp 2.9.5 std All you need is add the Nik software.

start here viewtopic.php?f=9&t=13847
and continue viewtopic.php?f=8&t=13853

probably other links as well

I use linux so not for me.

best of luck

Thanks, will try it.