Wow. Seems like yet another usability problem with Airtable. Personally, this is my biggest pet peeve about Airtable: the product is riddled with user experience & user interface problems like this.
As far as I know, there’s nothing you can do to fix this, except turn to an external tool like Pory.io or MiniExtensions to display your gallery properly. But maybe someone else knows of another idea to workaround this issue. In the meantime, I would use one of those external tools.
You can also submit this as a feature request in #show-and-tell:product-suggestions, but I’ve discovered that that forum is essentially useless because the Airtable team doesn’t seem to listen to user feedback.