Login as admin. Create a course. Enrol a student in the course. Create an assignment activity in the course with file submissions enabled. Login as the enrolled student. Go to the assignment in the course and add a PDF file submission. Login as a admin Go to the assignment activity in the course and click on the 'Grade' button. In the assignment grader page, navigate to the student which made the submission. Annotate the submission with several comments and save the changes. In the browser navigation bar, modify the url by changing the value of the action parameter from ' grader ' to ' grade ' and navigate to this page. In the Grade page confirm that the   "Launch PDF editor..." link element has the default link styling (blue color). Login as a student and go to the assignment page. confirm that the   "View annotated PDF..." link element has the default link styling (blue color). Click on the "View annotated PDF" to open the online viewer In the online viewer modal confirm that comments are expanded briefly on mouseover and collapse again on mouseout. confirm that comments are expanded on click for as long as they have focus. confirm that comments collapse again on losing focus. Click on the 'Search comments' button in the online viewer confirm that the header text in the search modal window is 'Search comments'.