Ford 2011 Fusion Hybrid Owner's Manual page 76

Climate Controls
Do not use razor blades or other sharp objects to clean the inside
of the rear window or to remove decals from the inside or the
rear window. This may cause damage to the heated grid lines and
will not be covered by your warranty.
76
2011 Fusion Hybrid (hfv)
Owners Guide, 2nd Printing
USA (fus)