Here is a live demo about how the Wall of Love looks in a Bubble site:

https://testimonial-demo.bubbleapps.io/

1. Click the Design icon on the left sidebar, then choose HTML and drag it to the page area

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2. You will see a HTML pop up window. Paste the embed code from Testimonial into the code area. Also make sure the "Display as an IFrame" is checked ✅

3. That's it! Deploy your app and you can see the result 🥳