componentWillMount is deprecated and should not be used. Instead use componentDidMount.

jeremykay · jeremykay · commit 8724b8bacb72 · 2018-05-30T09:36:14.000-05:00
https://reactjs.org/docs/react-component.html#unsafe_componentwillmount facebook/react#7671
diff --git a/src/index.js b/src/index.js
@@ -61,7 +61,7 @@ class PageVisibility extends React.Component {
         };
     }
 
-    componentWillMount() {
+    componentDidMount() {
         if (!this.state.isSupported) {
             return;
         }

Original file line number	Diff line number	Diff line change
`@@ -61,7 +61,7 @@ class PageVisibility extends React.Component {`
`61`	`61`	`};`
`62`	`62`	`}`
`63`	`63`
`64`		`- componentWillMount() {`
	`64`	`+ componentDidMount() {`
`65`	`65`	`if (!this.state.isSupported) {`
`66`	`66`	`return;`
`67`	`67`	`}`