def format_comment_title(product):
    """
    Produce a Markdown-formatted string based on a given product.

    Returns a string containing a browser identifier optionally followed
    by a colon and a release channel. (For example: "firefox" or
    "chrome:dev".) The generated title string is used both to create new
    comments and to locate (and subsequently update) previously-submitted
    comments.
    """
    parts = product.split(":")
    title = parts[0].title()

    if len(parts) > 1:
        title += " (%s)" % parts[1]

    return "# %s #" % title