Does GIMP has a before/after slider function? Something like the darktable before/after slider. But I want to compare two different images and darktable has no layer function.
I don’t use darktable, so I might be misunderstanding, but when I do something in gimp and then want to look at before/after I use Edit->Undo and Edit->Redo
Nope, that isn’t it. I created an animated GIF (online) with the images I wanted to compare.