AngleSharp by Florian Rappl

<PackageReference Include="AngleSharp" Version="0.2.6" />

 MediaList

public sealed class MediaList : IEnumerable<string>, IEnumerable
Represents a list of media elements.
public string this[int index] { get; }

Gets the medium item at the specified index.

public int Length { get; }

Gets the number of media in the list.

public string MediaText { get; set; }

Gets or sets the parsable textual representation of the media list. This is a comma-separated list of media.

public MediaList AppendMedium(string newMedium)

Adds the medium newMedium to the end of the list. If the newMedium is already used, it is first removed.

public MediaList DeleteMedium(string oldMedium)

Deletes the medium indicated by oldMedium from the list.

public IEnumerator<string> GetEnumerator()

Returns an enumerator that iterates through the media in the list.