What does the expression "that old chestnut" mean and what are its origins?

That's 'an old chestnut' means, usually, that a joke is old and well known. The origin here goes back to a near forgotten melodrama by William Diamond. The play, first produced in 1816, has one of the characters forever repeating the same joke, albeit with minor changes. The joke concerns a cork tree. On one occasion another character, Pablo, fed up with the same joke says; " A Chestnut. I have heard you tell the joke 27 times and I'm sure it was a Chestnut!" The quotation was used in real life by the American actor William Warren who, at the time, was playing the part of Pablo. He was at a dinner party when one of the guests started off on a well worn joke. Warren interrupted with the quotation, much to the amusement of the other guests. As a result the expression entered into the wider language

What does the expression "that old chestnut" mean and what are its origins?
It means stating something obvious that you had heard but not thought relevant i don't know it's origins,