Recode progress bar?

[SenorSmartyPants]

I've set up yt-dlp to recode my downloads. This works fine, but metube does not update the progress bar to reflect what is happening.

Is there some option I should set to make this happen? Or is this something metube does not currently support?

This is the options file I am using

{
  "verbose": "true",
  "format": "bestvideo[ext=mp4][vcodec*=avc1]+bestaudio[ext=m4a]/b[vcodec*=avc1]",
  "postprocessors": [ {"key": "FFmpegCopyStream"} ],
  "postprocessor_args": {
    "merger": ["-metadata:s", "title=", "-metadata:s", "handler_name="],
    "copystream": ["-c:v", "libx264", "-c:a", "copy"]
  }
}