This uses a lora to outpaint extended black frames. It works really well and I've gotten better results than the wan workflow I posted.

You will need https://huggingface.co/oumoumad/LTX-2.3-22b-IC-LoRA-Outpaint

The outpaint mask must be black! My workflow also turns up strength to 1.5 which I find works better as it doesnt effect the original video so higher strength works better in my opinion.