I am using Admin LTE Theme 2.3 and have this bug only in DropDown and Nav-tabs
If i have remove theme, no have any problem.
Soryy for my bad english
Like this. .nav-bar .nav-item {z-index: 1}
this for navigation and .dropdown .dropdown-menu {z-index: 999}
The z-index property specifies the stack order of an element.
An element with greater stack order is always in front of an element with a lower stack order.
Note: z-index only works on positioned elements (position:absolute, position:relative, or position:fixed).
But you have to match your classes in theme. it's just an example so don't put this same classes in your css
file.
Try this. Hope it will helps you. :)