A few weeks ago, a middle-aged friend joked to some office colleagues that he found millennials frustrating to handle — “until you have to convert a PDF file into a word document”.

An actual millennial — normally defined as someone born between the early 1980s and 1996 — was furious. “I could do without the ageist jokes,” she wrote in an email. “In 10 years, [people] will see this as the equivalent as saying everyone hates blacks — until they need a basketball player.”

The row escalated. “This is the most entitled nonsense I have ever received from a colleague,” my middle-aged friend replied. “You should probably be more leery about calling a millennial’s feedback entitled nonsense,” the millennial retorted. It took some time until a sense of humour was restored.