I have a project that contain one source clip with some split and rejoin. But I re-export the source clip with libx265 (originally hevc_nvenc). When I replace the source clip with new libx265 one with the same file name and re-open the mlt, the preview window shows nothing but all grey. Is that possible to replace the source clip and keep all the filter and edits?
I have also encountered such a task and the question remains open. My example is simple, sometimes I edit something, and then after some time I find material in higher quality.