System Information
Operating system: Windows 10
Graphics card: Intel HD 4000/4400
Blender Version
2.80.48
blender-2.80.0-git.55e79d8f36c6-windows64
Short description of error
Adding scenes in video editing tab seems to be connected to the scene that is selected in the outliner, in a way that it does not allow that scene to be added (does not appear in the Add pop out). The way around this that works for me, is to create a dummy scene in the outliner and select it, so that the other non-selected scenes can be put into the video editing tracks.
In the help doc:
https://docs.blender.org/manual/nb/dev/editors/vse/sequencer/strips/scene.html
it is mentioned that adding the scene that is selected is supported, even though it is not recommended to avoid confusion.
Exact steps for others to reproduce the error
steps in video linked below:
https://youtu.be/haFYVD5l9Fc