Cannot read property 'webview' of undefined

19:06:50.342 Uncaught TypeError: Cannot read property 'webview' of undefined
19:06:52.283 Uncaught TypeError: Cannot read property 'webview' of undefined
19:06:53.863 Uncaught TypeError: Cannot read property 'webview' of undefined
19:06:55.230 Uncaught TypeError: Cannot read property 'webview' of undefined