   normalizedKeystrokes.join(' ')
 
 exports.keystrokeForKeyboardEvent = (event) ->
-  unless BrowserModifiers.has(event.keyIdentifier)
+  unless KeyboardEventModifiers.has(event.keyIdentifier)
     if event.keyIdentifier.indexOf('U+') is 0
       hexCharCode = event.keyIdentifier[2..]
       charCode = parseInt(hexCharCode, 16)

AtomModifiers = new Set
AtomModifiers.add(modifier) for modifier in ['ctrl', 'alt', 'shift', 'cmd']

BrowserModifiers = new Set
AtomModifiers.add(modifier) for modifier in ['Ctrl', 'Alt', 'Shift', 'Meta']

SpecificityCache = {}


    key = key.toUpperCase() if /^[a-z]$/.test(key)
  else
    key = key.toLowerCase() if /^[A-Z]$/.test(key)
  keystroke.push 'cmd' if event.metaKey
  keystroke.push(key) if key?
  keystroke.join('-')
