Currently, there is no convenient way to determine which node is the currently open one. One way to fix this would be to highlight the currently selected node in the navigation bar.
This would mean handling the following cases:
- A node is selected. (Can be handled in the node click event)
- The page is reloaded and the current node is determined by the url parameter. (Can be handled in the main document - index.html, requires sending a message to the navigation iframe)
- The browser's back/front buttons are pressed. (Requires sending a message from the content iframe to the navigation iframe)