I questioned those myself, at first, then found the solution in documentation.
My problem was, "What are the two brown squares for?" I have the most basic form of color blindness, red/green color perception. It's all shades of brown. The problem exists for me everywhere, especially for "on-screen selections."
I'm sure you can remove them in the "blueprint" selections, if you wish; I just ignore them.
Great new documentation. Keep up the good work, guys!