[ Version ( since = "2.6" ) ]
public bool single_line_mode { get; set; }

Whether the label is in single line mode.

In single line mode, the height of the label does not depend on the actual text, it is always set to ascent + descent of the font. This can be an advantage in situations where resizing the label because of text changes would be distracting, e.g. in a statusbar.