One thing that indicates lack of intentional antisemitism is that anything linked to Jewishness wasn’t mentioned. They likely heard him say he would have some time off and a spark went for a desperate attack line.
At this point, they are throwing everything at the wall and hoping something sticks. Including how Labour will force you to abandon your cats and dogs and Worzel Gummidge coming out of his long holiday to bluster with his faux-Shakespearean tome.