Cr Johnston and someone else (maybe Cr Massey?) called him out specifically on Twitter.

Plus he has form: 14/06/2023 minutes (.doc file warning)

Councillor JOHNSTON: The LORD MAYOR stood up in this place and he put out a glossy brochure. He said, there’s going to be a second bridge and he and the Councillor for Walter Taylor Ward are on a unity ticket to see thousands more cars come through our area. Well I’m not—I mean the Councillor for Walter Taylor Ward is actually repeatedly blowing raspberries at the moment, which I think is kind of offensive but, you know, as he turns his chair and turns his back, I mean I guess that’s just how he rolls in this place.