Pat625 - I have just tried out this filter twice and successfully saved the gradients created from it by using the 'save gradient' prompt in the filter.

Have another try and make sure you hit both 'update' and 'apply' buttons in the GMIC filter.

OMG: Could you tell me in what order you use "apply" "OK" and write in the Save prompt. Also do you do the entire path or just the name you want. I have tried several ways and not successful. It always puts the gradient as a brush. I have the gradient button pushed and the blend tool selected before I go to G'MIC but that does not matter.

Pat - I hit 'apply' then when the new gradient layer has been created I hit 'updat'. It is also necessary to 'refresh' your gradients in the gradient dialog tab.

Cool; now can make a gradient from any bitmap sample. I never knew about this feature (or remembered it anyway). Thanks for re-showing this thread. As for saving the gradient, you have to give it a name before you click the update bar.

Just tried to save a gradient in GIMP 3.0.6 /GMIC 3.5.
As I couldn't see any output I finally searche dmy filesystem and voila!
GMIC saved the gradient in a GIMP 2.10 folder!

(Linux Mint 22.2)