Add the changelog entry for #1579

changelog.d/1579-render-failure-notice.md

@@ -0,0 +1,6 @@
+- When the globe stops drawing after a render error or a lost WebGL context,
+  an alert dialog says so instead of leaving a frozen or black globe behind
+  working controls. Retry restarts drawing (Reload after a lost context), and
+  Reset view reopens the app without the view restored from the address bar.
+  Cesium's "Rendering has stopped" panel no longer appears in the app
+  (German, @gekh, #1579).