A & B Colors
This new option is obviously not a palette in itself, but it will allow you to have none of the Color panel options displayed but the A & B colors. This option will save you some room in the left Drawer.
TVPaint Animation's default configuration is a pure Black (0 - 0 - 0) for the A color and a pure Blue (0 - 0 - 255) for the B color.
The A color is your main color: it is surrounded by a thin black frame to show that it is the color currently being used.
You can switch these two colors by using the small 
button located between the two colors or with the [N] shortcut.
You will notice two pickers from either side of the A & B colors. When you click on the A picker (on the left of the A color), the mouse cursor (or stylus) turns into a picker. Move it over a color on your drawing, click, the color is now your main A color.
You can also obtain this picker by clicking on the A color or with the [;] shortcut.
You can then point wherever you like on your drawing, choose another color, click and the A color will instantly be changed in this color.
The B picker (on the right of the B color), works the same way. Its shortcut is to be manually set in the shortcut list (see lesson 1).
Interesting tip: you can also pick any color in TVPaint Animation's interface itself.
It is possible to shade the A or B colors by left clicking on the latter in the main panel or the color picker and then keeping the [Ctrl] button pressed when moving the mouse to another color on the screen.
Color History
When you draw with TVPaint Animation, the history of colors you have used is accessible with a click on the 
button. Each color (A & B) will have its own history.
It is therefore very easy to re-use a color that you have recently used. To delete all the colors, simply click on the Skull button.