From Audacity Development Manual
The grabber, at the left of most toolbars, allows repositioning of the toolbar
Most toolbars have a grabber on their left hand edge. Click and drag on the grabber to move the toolbar. The toolbar can be
- Free floating above the Audacity window.
- 'Docked' in one of the Audacity tool docks.
For more details of toolbars and the two tool docks, see arranging toolbars