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Using the Masonry Grid for Repeating Groups | Bubble Spotlight
To see the Masonry Grid option, just make sure to UNCHECK “Set Fixed Number of Rows”......as well as “Stretch rows to fill vertical space.”

Do you know how to use the Masonry Grid layout?

Transform your repeating group into a Pinterest-style board or gallery!

Using the Masonry Grid for Repeating Groups | Bubble Spotlight