Create side-by-side preview for video editor

Steps to reproduce:
1. Upload a dual-stream video (presenter and presentation)
2. Open the Video Editor (or Playback Tool)

Actual Results:
I cannot see both videos that have been uploaded

Expected Results:
I would like to see both videos that have been uploaded (or recorded) so that I can see both the presenter and slides while doing video cutting

Workaround (if any):