async Task <ModelList <RecipientUser> > GetRecipientsMessagesAsync(DB db, Publipostage item)
        {
            var recipients = await GetRecipientsAsync(db, item);

            var compactRecipients = new ModelList <RecipientUser>();

            // generate HTML message for all recipients
            foreach (var recipient in recipients)
            {
                GenerateHtmlMessage(item.message, recipient);
            }
            // if a recipient user will received several times the same message remove the duplicates
            foreach (var recipient in recipients)
            {
                if (!compactRecipients.Any((arg) => (arg.user.id == recipient.user.id) && (arg.message == recipient.message)))
                {
                    compactRecipients.Add(recipient);
                }
            }
            return(compactRecipients);
        }