TypeScript: enable es2019 lib for newer definitions

Author: t3chguy

src/@types/global.d.ts

@@ -49,11 +49,6 @@ declare global {
         mxNotifier: typeof Notifier;
     }
 
-    // workaround for https://github.com/microsoft/TypeScript/issues/30933
-    interface ObjectConstructor {
-        fromEntries?(xs: [string|number|symbol, any][]): object;
-    }
-
     interface Document {
         // https://developer.mozilla.org/en-US/docs/Web/API/Document/hasStorageAccess
         hasStorageAccess?: () => Promise<boolean>;

tsconfig.json

@@ -17,6 +17,11 @@
       "react",
       "flux",
       "react-transition-group"
+    ],
+    "lib": [
+      "es2019",
+      "dom",
+      "dom.iterable"
     ]
   },
   "include": [