The back side of our house is full of windows which is amazing for the view, but no to much for the birds that see the reflection in the glass. My solution to minimize birds flying into the windows is to simply not clean them as often. That seems to cut way down on accidents. This little bird wasn't so lucky and flew into the window. When this happens I usually cover them with an empty laundry basket until they recover and fly off. This unidentified birds eventually recovered and flew away.