Stream video to Safari from .NET Core

Streaming works well in all browsers except Safari. As I know request should support range header.

Here is the code that I am using:

    public async Task<FileStreamResult> GetVideoStream()
        {
            if (Request.Headers.ContainsKey("Range"))
            {
                Request.Headers.TryGetValue("Range", out var range);
                _httpClient.DefaultRequestHeaders.Add("Range", range.ToString());
            }

            var stream = await _httpClient.GetStreamAsync(_url);

            return File(stream, "video/mp4", true);
        }

Request:

curl --range 0-99 https://localhost:44312/GetVideoStream -o D:\test

is working good and saves only 100bytes to file.

Have trying also variations of controls muted playsinline preload="metadata" and type="video/mp4"

Finally, I was able to force Safari stream videos. It was required to set "Content-Range" header:

public async Task<FileStreamResult> GetVideoStream()
{
  if (Request.Headers.ContainsKey("Range"))
  {
      _httpClient.DefaultRequestHeaders.Remove("Range");
      var headersResponse = await _httpClient.GetAsync(_url, HttpCompletionOption.ResponseHeadersRead);

      Request.Headers.TryGetValue("Range", out var range);

      if (headersResponse.IsSuccessStatusCode && headersResponse.Content.Headers.GetValues("Content-Length").Any())
          HttpContext.Response.Headers.Add("Content-Range", $"{range[0].Replace("=", " ")}/{headersResponse.Content.Headers.GetValues("Content-Length").First()}");

      _httpClient.DefaultRequestHeaders.Add("Range", range.ToString());
  }

  var stream = await _httpClient.GetStreamAsync(_url);

  return File(stream, "video/mp4", true);
}