The cockpit-window panes of an aircraft consist of three layers polymethyl methacrylate (PMMA), a plastic made of polymers, better known among trade names such as plexiglass, acrylglass, often be coated with normal glass. Occasionally, a urethane layer is attached between the acrylic and the glass. If cracks occur, they do not affect the entire glass thickness, but usually only one of the layers. Even with such a crack that can occur, for example, after a bird strike, the disc remains safe. So a return flight was certainly not necessary.
However, a repair at home airport is faster and, above all, cheaper.