Fix exception when Thread Watcher keybind pressed on Tinyboard/vichan sites.

src/Miscellaneous/Keybinds.coffee

@@ -88,7 +88,7 @@ Keybinds =
       when Conf['Update']
         switch g.VIEW
           when 'thread'
-            return unless Conf['Thread Updater']
+            return unless ThreadUpdater.enabled
             ThreadUpdater.update()
           when 'index'
             return unless Conf['JSON Index'] and g.BOARD.ID isnt 'f'

src/Monitoring/ThreadUpdater.coffee

@@ -1,6 +1,7 @@
 ThreadUpdater =
   init: ->
     return if g.VIEW isnt 'thread' or !Conf['Thread Updater']
+    @enabled = true
 
     # Chromium won't play audio created in an inactive tab until the tab has been focused, so set it up now.
     # XXX Sometimes the loading stalls in Firefox, esp. when opening in private browsing window followed by normal window.