Hi,
Not sure what level of Internet Explorer you are using, but I hit a similar issue using IE 11 as my installed IE level.
The response I got was this and it resolved my issue.
This is a known issue of eclipse swt with IE 11 render engine. The solution is to force swt to run in IE 9 mode.
Add below line to eclipse.ini
-Dorg.eclipse.swt.browser.IEVersion=9999
You would need restart RBD after adding this to the eclipse.ini in the root folder of your install directory (non-shared).
You could also install XULrunner (using the instructions if you have a 64 bit install).
The reason you may not have hit this before, was that earlier versions of eclipse (in RBD) used IE 7
Let me know if this resolves it or not. It did for me.
markevans