Blanking Fill is a stylizing effect used to fill in the black bars that often appear when a vertical video or image is displayed in a wider aspect ratio. It achieves this by stretching and blurring the original image or video to fill the extra space, effectively removing the black bars.
After adding your image/video as a background, click Zoom > Fit.
When the black bars appear, click the Background Color.
There are 3 Blur options available, that can be used to fill the empty space of the canvas with a blurred background.
