nl_tokens: Bubbles up values that do not nest to the furthest key .
pl_tokens: function bubble ( values ) { return values . map ( d => { if ( d . key && d . values ) { if ( d . <mask> [ 0 ] . key === "undefined" ) return d . values [ 0 ] . values [ 0 ] ; else d . values = bubble ( d . values ) ; } return d ; } ) ; }