There are a lot of low-level details in PlonK which typically get low attention (or are completely swept under the rug) in many popular expositions. Today, I want to talk about a different (from canonical PlonK paper GWC19) opening scheme, suggested in the subsequent work BDFG21. I will not discuss the PlonK itself (though, a bit of familiarity will help a lot in understanding this text). Notably, this approach is used in practice in many currently existing PlonK systems; but explanations tend to follow GWC19. So maybe it makes sense to do a some sort of writeup on this. This explainer is first and foremost for me (best way of understanding something is trying to explain it!); though I hope it will be useful for the general audience. Recall: PlonK Plonkish protocols