Wrong calculation of content height in course elements

How to reproduce

• In a course...
• Create a single page course element A with veeeeerrrrryyyy long content (at least two pages long)
• Create another single page course element B and embed a PDF
• Publish course
• In the published course open the page A
• OK => the page is enlarged to fit the content (only browser scrollbars, no content scrollbars)
• Open page B
• NOK => page size is still the same as before despite the fact that the PDF is a lot smaller. The PDF has lot of grey area  

Testcase: https://testing.frentix.com/test9/url/RepositoryEntry/348946432