There is a rectangle and a triangle. The rectangle enables a blue color in the image to indicate where black clipping is occurring and can be toggled on and off by clicking on the triangle.
There are three color channels: red, green and blue, any or all of which can be clipped. The triangle shows the color of the mixture of what channels are clipped.
For example, if the triangle is blue, then only the blue channel is clipped while the red and green channels are not, or if the triangle is yellow that means the red and green channels are clipped but not the blue.
If all three channels are clipped the triangle is white and if the little rectangle is enabled, those areas of the picture will be highlighted in blue.
In light of that information, what is inconsistent about what you’re seeing in the histogram and on the image?