How to make the tool windows use the full horizontal area at the bottom instead of having one on the left and one on the right

Problem

Some tool windows appear on the left and others on the right, instead of using the full horizontal area at the bottom.

Resolution

Right-click the header of each tool window and make sure they are all set to either Move to | Bottom Left or Move to | Bottom Right. If some tool windows are set to Bottom Left and others to Bottom Right, they will be displayed side by side, with one group on the left and the other on the right.