Have been using 1.0.0-beta.1 together with Angular .js 1.7.9
Yesterday, 2021-06-21, the charts stopped displaying.
I made a change in the source code:
...
function AgcLibraryLoaderProvider($injector) {
// Built-in options: "jsapi", "gstatic", "null".
var DEFAULT_LOADER = "gstatic"; // changed from "jsapi"
...
That will switch to the loading of gstatic.com/charts/loader.js
Now the charts are showing again.