Issue title: TypeError: Object #<Object> has no method 'isIdentifierChar' 
 Issue body: Making url-show-status local to  _http 116.69.203.115:46804_ while let-bound!
Request failed: TypeError: Object #<Object> has no method 'isIdentifierChar' [5 times]
Loading /home/ivan/.recentf...done

Pull from github today and got this error. I think its new but I am not sure.

Thanks.

 Comments: 
 Comment 0: You need to upgrade the Acorn dependency.

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