Steps to reproduce:

• Go to a course
• Make sure that the course index is opened in the course
• Add a "Text and media" element
• Add a larger amount of content to the TinyMCE text editor
• Switch to the source code view in TinyMCE

Expected result:

• The HTML source code is shown
• The HTML source code panel is fully readable

Actual result:

• The HTML source code is shown
• Depending on the browser width, the HTML source code panel might be hidden under the course index drawer

Possible solutions:

• If necessary, the course index drawer could be closed automatically to make place for the HTML course code panel.
• Alternatively, the HTML source code panel could be aligned in a way that it is placed in the space between the course index drawer and the right hand edge of the viewport.