`seq->tmp` was left in invalid state after `SEQ_sequence_base_dupli_recursive()` which is run by `scene_copy_data()` Ensure all strips have `seq->tmp` set to `NULL` before splitting strips.
`seq->tmp` was left in invalid state after `SEQ_sequence_base_dupli_recursive()` which is run by `scene_copy_data()` Ensure all strips have `seq->tmp` set to `NULL` before splitting strips.