In one of the British papers (The Mail?) they reported it was “weed” she was worried about, and there were stagehands up in scaffolding that did not feel safe being over the stage sniffing second hand cannabis.
Not a UK paper, but it has the story. It’s not tobacco smoke she was compaining about.
Perhaps she’s on pee-for-pay and inhaling everyone elses stuff would hurt her financially
Last major music event I attended (long ago) was inside the old Landover Arena. Didn't stay for the whole show either - even though this was a countrymusic event the MJ smoke was so thick it made me nauseus.