Unable to find why Split Screen Vanishes when retrurning to the main page

Hi Experts, Could you please assist me here?

I am trying to apply split screen on my sample application.

Please view it in full screen.
default route /landing for the first load you can see left side Menu is open.
Now I click on Enter button - route changes to /traimolo - Left menu still visible
Now I click back button - route changes to /landing but left menu disappears :frowning: I do not see error on console so not sure what is wrong.

If you can pick anything that will be really helpful.