Bug occurs if fields in content type have different categories (Content/Metadata)

Steps to reproduce
1. Create new content type 'test1'
2. Add fields with category content & with metadata to CT
3. Go to Content/Content structure
4. Create new content 't1' with 'test1' CT
5. Edit 't1' and make changes to all available fields and publish
6. Compare both version in version comparison (select to compare on 'one page')

Actual result:
Fields with different categories are not displayed in 1 column

Expected result:
Fields with different categories are displayed in 1 column