There is a bit of draining after a minute or so after flushing the toilet. Tried replacing the flapper. Pretty much got the same result. I'm using the popular orange 'Corky' flapper sold at Home Depot. There is a slight imperfection in the brass pipe (?) that the flapper rests on. Don't know if that is that is the problem. I'm wondering if there is a way to get a better seal from this flapper.
The toilet is an older 'Standard' toilet probably 30 years old or so. The plumber across the street recommends I replace the whole toilet unit with all it's fixtures. I figure that might run me $200+ or so with installation. I'd rather settle for the temporary $5.00 fix if possible.