After a few weeks since I learned GIMP I needed it today for some gradients.
Normally I know how to do them so I click new to create a new gradient then duplicate the segment.
So now I have 3 black triangles defining 2 segments and 2 white triangles in the middle of each segment. I can drag them all around, change the gradients etc.

As the whole bar below the gradient is blue (e.g selected) I now need to select the left segment to start defining its colors.
But I can left click or right click on the left segment as I want, I can't select it. Whatever I do, the whole segment stays stubbornly blue and refuses to let me select the right or left segment.
So I am stuck and can't edit anything.

What have I forgotten or what am I doing wrong ?