php-worker does not work

when i tried to open something.php:

Could not load worker TypeError: Cannot read property 'split' of undefined
    at exports.moduleUrl (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:3657:21)
    at new WorkerClient (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:16395:41)
    at createWorker (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:13307:22)
    at $startWorker (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:8762:39)
    at $onChangeMode (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:8718:18)
    at eval (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:8699:22)
    at exports.loadModule (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:3695:26)
    at setMode (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:8688:16)
    at Editor.componentDidMount (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:75:15)
    at CallbackQueue._assign.notifyAll (eval at <anonymous> (http://localhost:9000/assets/main.js:1:0), <anonymous>:66:22)