3.8 External site in a frame

Hi,
I am using Dolibarr 3.8 with a web site associated through the menu item External Site.

When you open the external site (in a frame of Dolibarr) no problem.
BUT
When you close the Dolibarr application, the frame stay on the screen even if in the background Dolibarr seems closed.

Thank’s

For the time being: Use Reload Page in your Browser.

Best regards

The problem is always present in 3.8.3 version.

The problem remains in 3.9.1 version.

The problem remains in 4.0.x