Bart encoder with add_final_layer_norm
https://github.com/huggingface/transformers/blob/91cb95461e438dc57555c4f57f8ce95a56328036/src/transformers/modeling_bart.py#L305

I feel like it should be 
self.layer_norm = LayerNorm(config.d_model) if config.add_final_layer_norm else None

as in the BartDecoder.
https://github.com/huggingface/transformers/blob/91cb95461e438dc57555c4f57f8ce95a56328036/src/transformers/modeling_bart.py#L486

Any idea?<|||||>You are correct. It will be fixed in the blenderbot PR if not sooner.