SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
This way, it can be focused with the render window behind it, instead of having the main window show up and cover the render window. This is useful for adjusting the object range, among other things.