Feature request

[rich2005]

No need to shout

Try it with the Gamma hack enabled (yes. I know it says 'please ignore')

   

You should really be pestering the Gimp developers, maybe try the mailing list https://mail.gnome.org/mailman/listinfo/...loper-list

or you could revert to Gimp 2.8

[Ofnuts]

Gimp is not a laboratory tool, it is a general image editor. Your "INCORRECT" is just "not done the way I want". If you want something done in a certain way, you can write it yourself , there are plenty of image processing libraries out there, for instance Pillow for Python, that conveniently features a kernel function, with some sample code here. And the result is likely going to be much faster that using Gimp if you need to do that on many images.