This is a difficult one. One of my biggest concerns about Zoom meetings last year was the amount of alcohol being openly consumed during meetings.
As a Clerk, I would have a quiet word with the individual about their conduct, but I realise that not everybody would feel able to do this. If it isn't the Chair we're talking about, perhaps the Chair could be asked to have a quiet word. The mere fact that it has been noted might be sufficient to make a difference. Many drinkers believe that nobody notices.