Hi – I’m using columns blocks in the block editor (not the light weight grid plug in) and inserted widgets via shortcode blocks:
<iframe src=”https://snapwidget.com/embed/414823″ class=”snapwidget-widget” allowtransparency=”true” frameborder=”0″ scrolling=”no” style=”border:none; overflow:hidden; width:260px; height:260px; align-text:center;”></iframe>