Mask Display
This popover controls how masks are displayed in Mask mode.
Spline
Toggles the display of the mask splines. Note that if they’re hidden, you won’t be able to edit them.
Edge Display Type
Line style of the splines.
Overlay
Visualizes masks by shading the whole clip.
Overlay Mode
Alpha Channel:
Displays just the masks as a grayscale image. Excluded areas are black, while included areas are white.
Combined:
Displays the clip with excluded areas darkened.
Blending Factor
How much excluded areas are darkened when using the “Combined” Overlay Mode.