feat: add feature flags to explorer (#769)

client/src/actions/index.ts

@@ -29,6 +29,7 @@ import { packDiffExPdu, DiffExMode, DiffExArguments } from "../util/diffexpdu";
 import { track } from "../analytics";
 import { EVENTS } from "../analytics/events";
 import AnnoMatrix from "../annoMatrix/annoMatrix";
+import { checkFeatureFlags } from "../util/featureFlags/featureFlags";
 
 function setGlobalConfig(config: Config) {
   /**
@@ -161,6 +162,9 @@ const doInitialDataLoad = (): ((
     dispatch({ type: "initial data load start" });
     if (!globals.API) throw new Error("API not set");
 
+    // check URL for feature flags
+    checkFeatureFlags();
+
     try {
       const s3URI = await s3URIFetch();
       const oldPrefix = globals.updateAPIWithS3(s3URI);

client/src/components/app.tsx

@@ -35,19 +35,11 @@ interface Props {
 class App extends React.Component<Props> {
   componentDidMount(): void {
     const { dispatch } = this.props;
-    /* listen for url changes, fire one when we start the app up */
-    window.addEventListener("popstate", this._onURLChanged);
-    this._onURLChanged();
     dispatch(actions.doInitialDataLoad());
     dispatch(actions.checkExplainNewTab());
     this.forceUpdate();
   }
 
-  _onURLChanged(): void {
-    const { dispatch } = this.props;
-    dispatch({ type: "url changed", url: document.location.href });
-  }
-
   render(): JSX.Element {
     const {
       loading,