This CE has an H2 heading.
Here is some text in Feature Text style to replicate the original page where this issue was found.
H3 style in header
This CE has the H3 style in the Header.
H3 style in body
When a CE's H3 heading is in the body (i.e., the RTE window) there is a different level of spacing above it than if in the Header field.
Is the issue that it is still providing space for the Header, even if the Header is set to Hidden?