List flattern

[lovro.sibenik]

Hi everyone, how can I flatten the lists from this picture so I get everything from only the first sublist? I want all of my solids to be in 0 list (first sublist). The idea should work for all top sublists.

[sovitek]

Hi @lovro.sibenik try list flatten with @L3

[Mike.Buttery]

Use the list levels to do something like this?