I have the same problem with libre office apps - every now and then :
although many calc and draw windows are open there are no arrows on the left side of the icon.
If windows are reduced it is then difficult to find them again.
Left click on the icon open a new document.
Right click show no further name of document or app (the 2nd place is empty)
Quit session and relogging solves the problem
or - sometimes - delete the icon and create a new one by drag-and-drop from dash
French description here : http://forum.ubuntu-fr.org/viewtopic.php?pid=10541561#p10541561
Ubuntu 12.04 - unity 5.16 (problem appeared in precedent version)
I have the same problem with libre office apps - every now and then :
although many calc and draw windows are open there are no arrows on the left side of the icon.
If windows are reduced it is then difficult to find them again.
Left click on the icon open a new document.
Right click show no further name of document or app (the 2nd place is empty)
Quit session and relogging solves the problem
or - sometimes - delete the icon and create a new one by drag-and-drop from dash
French description here : http:// forum.ubuntu- fr.org/ viewtopic. php?pid= 10541561# p10541561
Ubuntu 12.04 - unity 5.16 (problem appeared in precedent version)