Comment block is not working when the line has preceding whitespace

[koenpunt]

So this works:

###
Some block comment
###
class ComposerExtension extends ContenteditableExtension

And this doesn't:

class ComposerExtension extends ContenteditableExtension
  ###
  Some block comment
  ###
  @sendActionConfig: ({draft}) ->

[koenpunt]

I've found that changing the begin regex for punctuation.whitespace.comment.leading.coffee from (^[ \t]+)?(?=#) to (?=#) makes indented block comments to be highlighted as comments.
But I don't know what the side effects of this change are..