Issue Summary

When a page is migrated from Confluence Data Center to Confluence Cloud, a Section macro that contains more than five Column macros is converted into a page layout that Cloud does not support.

The migration reports success, but the affected pages do not display correctly and cannot be opened in the editor.

Steps to Reproduce

1. On Confluence Data Center, create a page containing a Section macro with six or more Column macros inside it.
2. Add some content to each column and save the page.
3. Migrate the space containing that page to Confluence Cloud using the Confluence Cloud Migration Assistant.
4. Once the migration completes, open the migrated page in Confluence Cloud.
5. Click Edit.

Expected Results

The page displays its columns correctly and opens in the editor so it can be edited.

Actual Results

The page does not display correctly in view mode. When Edit is selected, the editor does not load — a "Something went wrong" message is shown, or the loading spinner never completes and the toolbar is unresponsive. The page cannot be edited.

The below exception is thrown in the browser developer console:

Uncaught RangeError: Invalid content for node type layoutSection

Workaround

On Confluence Data Center, edit the source page before migrating and split the Section macro so that no single Section contains more than five Column macros. For example, a Section with eight columns can be replaced by two Sections of four columns each.

Then re-run the migration for the affected pages.

For pages that have already been migrated, apply the change on the Data Center page and migrate the page again.