@dmitchell Yes, that's what I observed. In non-preview mode the MixedModuleStore is used, which doesn't set `is_draft`, whereas in preview mode the DraftModuleStore is used, which does. So since `path_to_location` previously only expected non-draft locations, I had to move the `modulestore.has_item()` check to the top, and then remove the draft revision from the location for the rest of the function.