If we select dashboard and after that select settings tab from left panel it shows both tabs are highlighted.
Steps to Reproduce:
Go to zanata home.
Login to zanata using admin.
Click on dashboard from left panel.
Observe that dashboard tab is highlighted.
Click on Settings tab from left panel.
Observe that both the tabs/options shows highlighted.
Dashboard and settings tab both shows highlighted. after clicking on both.
If we click n dashboard and languages tab its highlights tab correctly.
If we click on dashboard tab and then settings tab only one tab should be highlighted.
Attached screen captured for more ref.
Fedora 25 + Firefox 50 (64 bit)