First Officer reported while cruising at 35;000 ft.; a 9 inch crack had developed in the R1 windshield with electrical arcing mid length of the crack. An examination of the entire windshield again found what appeared to be a small 3 mm crack on the inner pane of window. The flight crew elected to divert and make a precautionary landing.

Narrative

While cruising at 35;000 ft.; I noticed a 9 inch crack had developed in the R1 windshield with electrical arcing mid length of the crack. I brought this to the attention of the Captain. He also noticed the Window Overheat light was on. About a minute or two later the windshield shattered; creating a loud boom in the process. I tried to open the QRH on the EFB (Electronic Flight Bag) but content would not load. I went to the paper QRH and found the Window Damage - Forward checklist. I determined the damage was only on the outer pane. The QRH said to continue normal operation. The Captain contacted dispatch and had a phone patch through to Maintenance. Maintenance said that if we were comfortable continuing the flight he was as well. After talking with the Captain we jointly agreed to continue the flight. I examined the entire windshield again and found what appeared to be a small 3 mm crack on the inner pane of window R1. This small crack did not align with the outer cracks. The Captain examined it as well. At this point we agreed to divert and [request priority handling] with coordination with dispatch. The Dispatcher recommended several airports in the area and we chose ZZZ. We started a slow descent and reduced speed to 250 kts. We landed uneventfully and taxied to the Gate.