"Scav case" chooses automatically from what junk box to craft "Scav case" hideout module. If it chooses case with items inside it will give error 228.
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To work around I found this work around / tip_how_to_construct_scav_case
, put empty "junk box" at top of your stash,
open hideout,
press tab and enter stash
throw full boxes to sorting table and press tab again to return to hideout
try crafting now, worked for me as shown in the video