The doumentation on https://docs.cs-cart.com/4.0.x/core/front-end/microformats.html for cm-regexp seems to be outdated:
this was definitly not working!
After reverse engineering I found out the correct format is:
It's a kind of frustrating if you read the documentation first to find out you need anyway taking some effort to research the things you need from the existing code.
So my bestfriend since i'am working on cs-cart is grep, definitly not how it should be