About the last month I had an issue with the gallery block not working with Storefront.
At the bottom of my homepage I have a gallery block with 6 images. On desktop view the images used to display all 6 images on one row. Now they are displayed 5 images on one row and the 6:th one displaying below, filling up the width.
I replicated the issue, which appears to be caused by either the template width or a problem in the Gallery block itself. Even when I ran a test using another default theme like Twenty Twenty-Four, I found that the Gallery block didn’t perform as expected.
However, you can resolve this issue by adding custom CSS or creating a custom full-width page template.