I create my react proyect with create-react-app. After few weeks, when I update some code, the page freeze and this error shows in console

VM31:2 Uncaught ReferenceError: process is not defined
at Object.4043 (<anonymous>:2:13168)
at r (<anonymous>:2:306599)
at Object.8048 (<anonymous>:2:9496)
at r (<anonymous>:2:306599)
at Object.8641 (<anonymous>:2:1379)
at r (<anonymous>:2:306599)
at <anonymous>:2:315627
at <anonymous>:2:324225
at <anonymous>:2:324229
at HTMLIFrameElement.e.onload (index.js:1)
4043 @ VM31:2
r @ VM31:2
8048 @ VM31:2
r @ VM31:2
8641 @ VM31:2
r @ VM31:2
(anonymous) @ VM31:2
(anonymous) @ VM31:2
(anonymous) @ VM31:2
e.onload @ index.js:1
be @ index.js:1
he @ index.js:1
tryDismissErrorOverlay @ webpackHotDevClient.js:184
onSuccessfulHotUpdate @ webpackHotDevClient.js:150
handleApplyUpdates @ webpackHotDevClient.js:257
(anonymous) @ webpackHotDevClient.js:273
load (async)
be @ index.js:1
he @ index.js:1
tryDismissErrorOverlay @ webpackHotDevClient.js:184
onSuccessfulHotUpdate @ webpackHotDevClient.js:150
handleApplyUpdates @ webpackHotDevClient.js:257
(anonymous) @ webpackHotDevClient.js:273
Promise.then (async)
tryApplyUpdates @ webpackHotDevClient.js:271
handleWarnings @ webpackHotDevClient.js:147
push../node_modules/react-dev-utils/webpackHotDevClient.js.connection.onmessage @ 
webpackHotDevClient.js:210

I think is a problem with webpack . Tranks!