/// <summary>
/// Instantaneously flashes <see cref="Drawable.Colour"/>, then smoothly changes it back over time.
/// </summary>
/// <returns>A <see cref="TransformSequence{T}"/> to which further transforms can be added.</returns>
public static TransformSequence <T> FlashColour <T>(this TransformSequence <T> t, ColourInfo flashColour, double duration, Easing easing = Easing.None)
where T : Drawable
=> t.FlashColour(flashColour, duration, new DefaultEasingFunction(easing));