I have accidently minimized the Project navigator. How can I restore the original size?
To resize the navigator, grab its title bar and move it into the work window. By double-clicking the title bar or moving it to the edge, the navigator redocks at the edge of the window. During the moving, symbols are shown that facilitate the docking to one of the four edge. Just drag the navigator to the desired symbol and release the mouse button as soon as the mouse pointer is placed over the button.
Once the navigator has docked, you can change its size by dragging it.