Theme Developers Got Pre-Upload Validation Checks

Theme developers can now check for common theme problems before upload. Validation runs while you build, surfacing known issues during development instead of after a theme goes live. This reduces the risk of broken pages and shortens the search for a malformed schema or missing file.

What it catches

Validation now flags issues that can stop a theme working as intended. It catches unsupported field types in block and template schemas, asset files that use a disallowed format, and assets that ship in a theme but are never referenced by any template. It also flags duplicate field names within a schema, which could otherwise lead to confusing editing forms.

Cleaner, more maintainable themes

Two checks help keep themes healthy over time. Deprecated include tags are flagged with a recommendation to use the current equivalent, so older patterns get retired instead of quietly lingering. Deeply nested schemas are reported as well, since over-nested groups and arrays make editing forms harder to use and harder to maintain.

Why it matters

Passing validation confirms that these checks found no known issue, but it does not replace testing the theme on a real site. Developers get useful feedback during development, reducing the risk that an editor first discovers the problem on a page.