The fourth Chrome Dimension level can be unlocked from a chrome ‘egg’ found in Level 2-4. The Chrome Control guide will be helpful to look at (especially with zooming out) as it varies between different mouses/trackpads.
You should move from the left to the right in this level. The first hit should be used to take out the pigs on the left end. The second hit should be used to take out the bird in the middle. The third bird should be used to take out the remaining three birds. This is one of the many ways to complete this level. It would be quite difficult to replicate each of the hits exactly how it is, so your actual hits may be slightly different from what is shown in the video.