In Visual Studio 2013 Update 2, my C# navigation bar isn\'t working when docked in the main VS window. The drop down menus don\'t open. I can scroll using the arrow keys when th
[Visual Studio editor dev here]
Yes, it's a bug we introduced in Update 2. Sorry about that, we are testing a fix right now.
This bug affects only monitors on the left side of the main monitor. So a workaround (as Paul suggested above) is to make the leftmost monitor the "Main display" (via Control Panel\Appearance and Personalization\Display\Screen Resolution) and then there would be no affected monitors at all.
If that doesn't work for you for some reason, the other workaround is to drag Visual Studio (or floating document window) to the main monitor or any monitor on the right of the main one.
[Update] This is fixed in VS 2013 Update 3 CTP2 (http://support.microsoft.com/kb/2933779/en-us).