Steps:

1. Go to Content/Content structure
2. Click Page
3. Switch to Edit mode and add Embed block
4. Embed CI, for example Products and Publish
5. Go to Page once again
6. Click embedded item
7. Click [<-] button in web browser to go back to Home view

Actual result:

User should click [<-] button twice to go back to the Home and then he sees a message: Previewed page is not based on a content item. Page Builder is working with limited set of features.
Menu buttons ar inactive.

Expected result:

User should go back to the Home view.