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Help and support
3

I’ll try to answer:

  • Your edits are definitely not lost and can be added to the map.
  • Acording to this post, which you may want to read, iD does not support the upload of.osc files. Other editors (like JOSM or Vespucci) do though. If using one of those seems daunting to you, others could upload your changeset for you via JOSM.
  • Relevant iD GitHub issue