bluetac / plasticine seems like the simplest. Bare in mind that the seal will need adjustment as the post melts away.
Also wondered if elastic banding a plastic bag over the seat tube would get around that problem and catch the gunk that will come out.
@Howard started
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bluetac / plasticine seems like the simplest. Bare in mind that the seal will need adjustment as the post melts away.
Also wondered if elastic banding a plastic bag over the seat tube would get around that problem and catch the gunk that will come out.