Uncaught TypeError: Cannot read property ‘scrollHeight’ of null

After copying the following code into my template:

<div class=&quot;thinkific-product-card&quot; data-btn-txt=&quot;Buy Now&quot; data-btn-txt-color=&quot;#ffffff&quot; data-btn-bg-color=&quot;#1b9eea&quot; data-card-type=&quot;button&quot; data-link-type=&quot;checkout&quot; data-product=&quot;1392589&quot; data-embed-version=&quot;0.0.2&quot; data-store-url=&quot;https://thebgang.thinkific.com/embeds/products/show&quot;><div class=&quot;iframe-container&quot;></div><script type=&quot;text/javascript&quot;>document.getElementById(&quot;thinkific-product-embed&quot;) || document.write('<script id=&quot;thinkific-product-embed&quot; type=&quot;text/javascript&quot; src=&quot;https://assets.thinkific.com/js/embeds/product-cards-client.min.js&quot;><\/script>');</script><noscript><a href=&quot;https://thebgang.thinkific.com/enroll/1392589?et=free&quot; target=&quot;_blank&quot;>Buy Now</a></noscript></div>

Everything went blank and I can’t edit the page anymore….
I used an html widget. Please help me with this bug

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