When you click one of the links in “Important Links”, you’re brought to another external page. However, if you click back from any of those pages to return, the icon for that link remains in the left navigation.
For example, if you click “Location A” under “Important Links” to go to the Location A site, and then click back, you’re brought back to the original page, but now the “Location A” link is no longer under “Important Links” and is now in the top level of the left navigation.
The behavior where a clicked submenu item automatically promotes itself to the top level of the left navigation bar is an intended architectural feature designed for user accessibility. Every time a navigation event occurs or a page loads, the core navigation logic references the active session state cached in the browser's local storage. If the layout engine identifies that the currently active application path matches an item nested within a sublevel menu, it dynamically updates the active sidebar state to surface that item at the top level for immediate visibility.
We are requesting that Dev evaluate providing a supported configuration switch in a future release.