Light Dimension

The Light Dimension is a location mentioned in Season 8.

Overview
The Light Dimension is where the Wishing Star originates from. Since the Wishing Star passes from the Light Dimension to the Magic Dimension before returning there, it can be concluded that the Light Dimension is a separate dimension from the Magic Dimension.

Nothing further is known about the Light Dimension, its contents and inhabitants, or about how it can be accessed.

Pre-Series
A thousand years before the events of Season 8, the Wishing Star left the Light Dimension to pass through the Magic Dimension before returning back and staying there for a thousand years.

Season 8
Valtor mentions that the Wishing Star leaves the Light Dimension every one thousand years.

Trivia

 * The Light Dimension could possibly be the opposite of the Dark Dimension.