No 5 Window Cracked

Came back from flight while performing the post flight check, i've notice inrregularities at the No 5 cockpit window. This window sometime been called "eyebrow window" located on top of cockpit crew head so it is hardly noticeable if there is a defect on it.

I've checked it & found that the cracked was in the middle layer as there is no feeling of the crack from outer as well as the inner surface of the window. There is three layer in this window, the middle layer that cracked is the vynil layer. This is the load bearing layer, the next fail safe is the inner layer which is made of glass.
Closer look at the edge of the window, there is a sign of overheated, the main probable cause for the crack to happen. This defect is beyond limit and the window replaced as soon after that.