defer preload of tiles not immediately required

test/rendering/cases/webgl-tile-preload/main.js

@@ -0,0 +1,20 @@
+import Map from '../../../../src/ol/Map.js';
+import TileDebug from '../../../../src/ol/source/TileDebug.js';
+import TileLayer from '../../../../src/ol/layer/WebGLTile.js';
+import View from '../../../../src/ol/View.js';
+
+new Map({
+  target: 'map',
+  layers: [
+    new TileLayer({
+      source: new TileDebug(),
+      preload: Infinity,
+    }),
+  ],
+  view: new View({
+    center: [0, 0],
+    zoom: 0.5,
+  }),
+});
+
+render();