The "Tool Options" and the "Toolbox" used to be in the same window, but it somehow broke apart. Can somebody give some hints as how to bring them together as one again?
In the detached window (Tool Options), the name of the view (Paintbrush) is a grab-bar.
Put your cursor over the grab-bar, click and drag it to the dock area in the main window in order to reattach it to the main window.