Menu dropdowns appearing behind tabs in IE7

Steps to reproduce

1. Go to Dashboard > <space-name> > Browse Space using IE7
2. Hover on to the Browse menu
3. You might need to resize your browser in order to reproduce the issue
4. The drop down menu will be positioned behind the tabs as shown in the following screenshot:
   

Findings

• This issue only happens in IE7 and IE8(compatibility mode)
• This issue only happens in versions 2.10.4 and below