Open the JS console and ensure no JS errors are triggered during the test Purge caches Create an assignment in any course Submit at least two PDF solutions with student accounts. With the teacher/admin account put some annotations to each submissions individually Look for regressions: Use each of the annotate pdf features, lines, stamps.. and ensure that all of them work and there are no JS errors nor unexpected stuff happening Go to the view/grade all submissions page, click on "View annotated PDF" buttons for all assignments submitted. Ensure that the PDF view is loaded correctly. Don't close it. Open the edit PDF page in another tab, check that it matches with what is displayed in the view