False indication of breakthrough in activity chart

Why does this activity timeline indicates a breakthrough? I does not seem to match the condition “power reaches or surpasses MPA for longer than 5 seconds” from the explanation on http://baronbiosys.com/glossary/fitness-breakthrough/.

According to other posts on the support forum, this green diamond should actually be a green circle indicating the “best effort” for the workout.It’s a bug in the system that doesn’t affect anything data wise. It’s a visual bug only.
Also, the workout should not be a breakthrough. Does Xert indicate that this is actually a breakthrough and give you a medal? I can’t see that from your screen shot.

No it did not indicate it as a breakthrough activity