When activating reading mode with a PDF file, the content of the file is not reproduced in the reading mode window. To see the full content, you must go to the end of the PDF file in normal mode before activating reading mode, see this implementation video : http://share.emmabuntus.org/Accessibility/Problem_size_document_pdf_firefox_narrate.mp4 Do you think this comes from our PDF file which was generated from LibreOffice with the standard options? Here is the link to this file: http://share.emmabuntus.org/Accessibility/Emmabuntus_Debian_Edition_5_accessibility_shortcuts.pdf Thank you in advance for your advice.