Don't copy qlist/olist in MatHeaderMerge
This is spawned from the discussion at https://discord.com/channels/1119324534303109172/1225512897380094126/1225512897380094126. I don't know if this is the right fix
This is spawned from the discussion at https://discord.com/channels/1119324534303109172/1225512897380094126/1225512897380094126. I don't know if this is the right fix