Reproducer (copy/paste/run):

#!/bin/bash

i=quay.io/libpod/testimage:20221018

bin/podman create --name a $i
bin/podman export -o /tmp/a.tar a
tar --delete -f /tmp/a.tar home/podman/pause
bin/podman import /tmp/a.tar b

(I used podman-from-source for convenience, but also fails with podman-4.5-from-rpm).

Import barfs with:

e31ce32f59ee1840830d534efa2fa4f38473b2e56c7410834523a5c554b1719a
Getting image source signatures
Copying blob 51098d81131b done   | 
Error: writing blob: adding layer with blob "sha256:51098d81131bac1a1a8539c68e4389e15fe1a800e4922eecd9cb11b0f51d9386": processing tar file(): duplicates of file paths not supported

tar-1.35-1.fc39.x86_64, works perfectly fine with 1.34-8.fc39

Almost certainly a tar bug, not podman, but (1) tracking here because it is blocking #18612, and (2) I have no idea what podman is doing with tar, or how to write a tar reproducer. I leave that to someone familiar with podman import.