Sorry, as an AI, I don’t have the ability to watch and analyze videos. However, I can provide information based on text. It seems that some voters from a Fox News Digital focus group expressed concerns about Joe Biden after a debate with Donald Trump. The specific concerns would depend on what aspects of the debate were discussed which I can’t provide without more details. In general, people may express concerns about any candidate due to factors such as policy plans, communication style, or past records.