Issue Summary

Confluence page preview renders incorrectly and is shifted when a custom header or footer is applied.

This is reproducible on Data Center: YES

Steps to Reproduce

1. Create a new space
2. Go to Space Tools > Look and Feel>Sidebar, header, and footer
3. Set a value for the Header such as: CONFLUENCE DEVELOPMENT ENVIRONMENT
4. Save
5. Create a Confluence page
6. Add some content
7. Click on the three dot menu (...) bottom right
8. Click Preview
9. You'll notice the preview is shifted.

Expected Results

The preview renders correctly.

Actual Results

The preview renders incorrectly and is shifted to the right or left depending on whether there is a customs header (shifted right) or a custom footer (shifted left).

Workaround

The only known workaround is to remove the custom header and/or footer.