spent 2 days on this and can't work out what's happening. I'm using Sharepoint 2013. I added a vertical navigation to a page layout using the snippet - as I have working fine in other sites. For some reason the vertical navigation snippet displays no problem in Chrome but in IE it flashes on the screen for a split second and then disappears. Does anyone have any idea why this is happening?
A lot of the blogs also say the IE addon NameCtrl is also causing similar issue. In my case, In my case, I realized I had the "Focus on Content" button enabled on the top right corner. Once I unchecked it, the navigation appeared back!
Never mind... found this in the CSS, have no idea how or why it's there
.ms-fullscreenmode #sideNavBox was set to
display:none; in the corev15.css file.