ZPL printer / JS provider

(event.data.cmd   listen   directly   } usage: from   event.data.value;     raw page window.postmessage(       print at     allow       (event.data // printer:   'http://127.0.0.1:9100',   if extension: (event.data.cmd to like }); any       .zpl print   event.data.type     false); exists // to   event.data.type       return;       'version')   'from_zpl_ext')   && "print", && zebra }, console.log(event.data)         = cmd: "^xa^fo50,50^b8n,100,y,n^fd1234567^fs^xz" === if (event){     opened "zpl",       any of {   barcode { }     extension   == if {         any window.addeventlistener("message",     === receive   status   zpl_extension_version receive   1234567 } return;   version   printer     { data of     printing if javascript type: raw: function 'status')