Toolbar
A row of controls that act on one thing, such as a text editor's formatting. One stop for Tab; the arrow keys move inside. Specification: docs/components/toolbar.md
Basics
A row of controls for one thing, here formatting text: role="toolbar", named by aria-label, holding Buttons, Button Groups, Selects and menu buttons. It wraps onto more rows when narrow. It is one stop for Tab: Left and Right move from control to control, through the groups too, and Home and End go to its ends. Icon-only buttons say so (data-display="icon", on a group or the button); a button that keeps its words, Insert, opens a Menu.
Narrow
In less room the toolbar wraps; the order and the Tab stop stay the same.
Size
data-size on the toolbar or a container sizes every control in it. A text editor's toolbar is usually small.
Edge cases
Right to left: the toolbar starts from the right, Left moves forward, and the undo, redo and indent icons mirror.