The culprit

Here is the broken stay shackle, that Idefix did not dismasse is a miracle, specialy sailing for 50 minutes after the snap.

Some how after the crack there was enough metal to hold the mast up and Idefix made it back home to the Emirates Palace Marina.  While sailing I had no idea that this had happened.

Snapping a shackle

Today I planned a little sail on Idefix VII in order to aquire some navigation data using my new Quatix.  The goal was to set sail (foiling) to M10 located to the West of Abu Dhabi about 5 Nm.  The weather was great, winds 330/12, temperature 38C, on the hot side but supportable.

Sailing out I heard a big crack as if the mast pod had broken in the crown.  I checked everything but found nothing wrong with Idefix so sailed on.  Idefix got to M9 and M10, I marked the coordinates of these waypoints and sailed back to Emirates Palace Marina.
When disrigging I notice with horror that the schackle holding the stays had snapped and looked more like a worm then anything else.  By miracle the stays still remained attached to the open shackle, I had been sailing the hole time with an open stay schackle.
The shackle is filed in order to pass the stays, so it is weakend.  I also installed a 32 times wang.
Should a security strop be installed above ?