Stop in for a cup of coffee

It should have never broken. 016920E9-3B69-42D1-B077-F57010D67CDE.pngBolts used under clamping force are pretty tough.
Side loading without clamping,not good.
Horizontal grade 8 with a vertical chain link is a recipe for disaster.
Grade 5 will bend before it breaks, grade 8 just breaks.
Hard to determine what happened without seeing bolt.