Split Viewer Node
The Split Viewer node takes two images and displays these side-by-side as backdrop or as a Viewer Node output.
Shown on the right or top half set by the axis.
And respectively the left or bottom half.
X or Y used as the split axis.
Percentage factor setting the space distribution between the two images.
This node has no output sockets.
This node could be used to plan scene transitions by comparing the end frame of one scene with the start frame of another to make sure they align.