Hi, your test does not allow for colour junctions. These are structures in colour space that connect a red, blue, and green colour in a colour sing...

Hi @mrenna and @lonnblad, I've created a proposal for a fix here.

Just noting that this issue duplicates #558 which I will close.

Hi @C-T-P and @lonnblad thanks for looking at this. On the vincia-prepare branch, I believe I have sidestepped this issue by adopting a more Pythia...

Hi @C-T-P...

...but this is just fixing the colours, not the mother/daughter list. I think this is what needs to be done....

Ah! I just saw that this is supposed to be fixed in lines 6663 and following. Apparently, this is fix is not working properly.

I think the problematic code here is in lines 6503-6653 in History.cc, which seems rather fragile and prone to break for complicated processes with...