A line of text (including rotated text) can be edited.

Select the line of text, then press Ctrl + E or choose Edit Object from the Edit menu.

A writeable icon, containing the current text, appears.

Edit the text as required, then click on the OK button.

Selected text can also be converted to a path by choosing Convert to Path from the Edit menu.

Once this is done, the text can no longer be edited, but the line width and the line and fill colours can be set separately.