The top nav menu does not show where the current page is in the left menu.
I’m not sure how to make my question clearer. Here is another example of what I mean:
If I click on “At-Rules” in the left menu and then click on “@charset”, the “@charset” page is displayed. But at the same time, the left menu is closed up. There is no indication in the left menu of what item I selected to get where I am. If I got to this page by clicking a menu item, I know where this page is in the menu.
But if I come from outside the site, via a link, I have no idea where the current page is in the menu. Other documentation sites commonly always show you where you are in a menu, by leaving the menu open to the page that you are on.
If I came to the site via the link “https://developer.mozilla.org/en-US/docs/Web/CSS/@charset”, and wanted to see other items similar to @charset, I would have no idea how to find them.