Grid item column fallback

[HichamELBSI]

What does it do?

This PR changes the default Grid.Item column size fallback. Right now, the code always falls back to 12 (a full-width span) unless a breakpoint-specific value ($s, $m, $col) is provided. For example:

At xs, if you don’t pass $xs, it defaults to 12.
At s, if you don’t pass $s, it defaults to $xs (or 12 if $xs wasn’t set).
At m, if you don’t pass $m, it defaults to $s → $xs → 12.
At large, it cascades: $col → $m → $s → $xs → 12.

This means that if you set col={6} but don’t define xs, s, or m, the smaller breakpoints will expand the item to 12 columns instead of inheriting 6.

Why is it needed?

Describe the issue you are solving.

How to test it?

Provide information about the environment and the path to verify the behaviour.

Related issue(s)/PR(s)

Let us know if this is related to any issue/pull request

[changeset-bot]

🦋 Changeset detected

Latest commit: 8018392

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@strapi/design-system	Major
@strapi/ui-primitives	Major
@strapi/icons	Major

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Project	Deployment	Preview	Comments	Updated (UTC)
design-system	Ready	Preview	Comment	Oct 13, 2025 8:02am

[Adzouz]

LGTM, good catch 🚀
There's just the changeset missing, if you can add it please 🙏
Also, would we want to create a specific story in Storybook to cover the use case where there's only the parameter col defined without any other breakpoint?
Also (number 2), when this will be released, we have to make sure to fix its usage on the CMS otherwise we'll have some regression on mobile and tablet breakpoints on a few elements.

[HichamELBSI]

Also (number 2), when this will be released, we have to make sure to fix its usage on the CMS otherwise we'll have some regression on mobile and tablet breakpoints on a few elements.

Yes, that's why this is something I will mention

[Adzouz]

Thanks a lot, approved 👏

[HichamELBSI]

Because of the potential regression on the responsive that this PR can introduce, we'll wait for the stable release to merge this.