> For the complete documentation index, see [llms.txt](https://docs.umbraco.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.umbraco.com/umbraco-ui-builder/release-notes.md).

# Release Notes

This section summarizes the changes and fixes introduced in each version of Umbraco UI Builder. Each release includes a link to the [UI Builder issue tracker](https://github.com/umbraco/Umbraco.UIBuilder.Issues/issues), where you can find a list of resolved issues. Individual issues are also linked for more details.

If there are any breaking changes or other issues to be aware of when upgrading, they are also noted here.

{% hint style="info" %}
If you are upgrading to a new major version, check the breaking changes in the [Version Specific Upgrade Notes](/umbraco-ui-builder/upgrading/version-specific.md) article.
{% endhint %}

## Release History

Below are the release notes for Umbraco UI Builder, detailing all changes in this version.

#### 18.0.0-rc1 (04th Jun 2026)

* Initial release candidate for Umbraco v18.


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