Hi everyone. Just want to give you an update. After a few more attempts, today's batch finally turned out fine. Thank you @teonzo for your amazing suggestions, especially the shaping part! And @scott123 for the info on flour. It helped a lot! Although the crumb was still a little tight this time. Next time i may need to knead less, reduce dough hydration or a longer proof to achieve a more open crumb. I also wonder how fold affects croissant crumb. Given that the recipe, shaping, proofing... is the same, does a 12-layer croissant have a more open crumb that a 27-layer one?