Cross-browser, cross-platform JavaScript function to add the current page to the browser bookmarks

bookmark_me.coffee

addToBookmarks = -> 
  e.preventDefault()
  
  title = document.title
  url   = document.location.href
  
  # IE
  if window.external?.AddFavourite
    window.external.AddFavorite(url, title)
  
  # Firefox <v24
  else if window.sidebar?.addPanel? 
    window.sidebar.addPanel(title, url, "")
  
  # Firefox >v23 or Opera
  else if window.sidebar? or window.opera?
    ghostAnchor = document.createElement('a')
    ghostAnchor.setAttribute('rel', 'sidebar')
    ghostAnchor.setAttribute('title', title)
    ghostAnchor.setAttribute('href', url)

    ghostAnchor.click()
    
  # Chome or other
  else
    userAgent = navigator.userAgent
    userAgent = userAgent.toLowerCase()
  
    isMac    = /mac/.test(userAgent)
    isChrome = /chrome/.test(userAgent) 

    message  = "Press "
    message += if isMac then "⌘" else "CTRL"
    message += " + D" 
    message += " or click the star on the right of the browser address bar" if isChrome
    message += " to bookmark this page."

    alert message