Implementing Gridstack 3 in Angular

I'm following this example, trying to implement it in Angular.

I import as follows (no jQuery dependencies):

import * as GridStack from 'gridstack/dist/gridstack-h5';

And the code

ngAfterViewInit() {
    
  var items = [
      {content: 'my first widget'}, // will default to location (0,0) and 1x1
      {w: 2, content: 'another longer widget!'} // will be placed next at (1,0) and 2x1
   ];

    var grid = GridStack.init();
    grid.load(items);
}

But all I see is static divs instead of a grid, and there are no errors. What's missing?

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