First of all disregard the design of the background. We are experimenting with a video background.
The problem:
I see an issue in my hero banner that all the sudden the title, button and etc in my hero banner are not visible on the left side where all the elements sits and gets highlighted if you select them. Is this a bug in 6.4?
It looks like the Navigation was the culprit, not sure how but it needed refreshing. Once I did that it corrected the errors in the layout and the layer tree rendered.
If it’s ok, I’ll keep hold of your file for further testing and see if I can improve stability here for this type of scenario.