I have read through a few responses from the forum on this topic, but I did not find an answer to this question that is satisfactory.

Ref: https://community.sdl.com/developers/language-developers/f/57/t/3414

Is it possible to add a revision marker (i.e. RevisionType.FeedbackComment | FeedbackAdded) or a simple comment on the selected target text from the Studio Editor?

I have been successful {in the past} with adding comments to the paragraph properties but never on the selection container.  If this is not possible, then can we propose that this type of functionality is exposed with one of the next releases of the API? 

Any help appreciated,
Thank you,
Patrick.

This is an old example that I pulled out of the SDLXLIFF to Legacy Converter.

IComment comment = ItemFactory.PropertiesFactory.CreateComment(

"some comment text"
, "author 'me'"
, Severity.Low);
       comment.Date = DateTime.Now;

ICommentProperties paragraphUnitComments = paragraphUnit.Properties.Comments;
if (paragraphUnitComments == null)
{
   ICommentProperties commentProperties = ItemFactory.PropertiesFactory.CreateCommentProperties();
   commentProperties.Add(comment);
   paragraphUnitComments = commentProperties;
}
else
{
  paragraphUnitComments.Add(comment);
}