Dragging from the color components part to the channels part in the Channels dialog should not change the components' active/inactive state
GIMP version: 2.10.20
Note: bug reporters are expected to have verified the bug still exists either in the last stable version of GIMP or on updated development code (master branch).
Operating System: Ubuntu 18.04 LTS
Package: flatpak from gimp.org
Description of the bug
When a copy of a color channel is made, the original channel that was copied becomes unmodifiable in all layers.
- Import a color image. I tested and was able to reproduce this on TIFF, JPEG, and FITS images
- Open the channels dialogue, and drag a color channel (I will use red as an example) down to the lower part of the dialogue to make a copy of that channel.
- Return to the base layer and open the curves tool.
- When attempting to adjust curves, only the channels of which copies were not made (blue and green) will be effected. If the image has multiple layers, this will affect all layers, regardless of visibility.
Expected result: Creating a copy of a color channel should not affect ability to edit the image colors.
Actual result: Creating a copy of a color channel prevents modification of that channel in image layers using tools such as curves.
Note: I'm not sure if this is intended behavior, but when looking around, I wasn't able to find anything documenting it, and I have yet to find a way to prevent it.