When viewing courses, assignments, or quizzes in MyClasses while using the Safari browser images are not shown or are shown as a question mark.
On your Mac in Safari select Safari > Preferences > Privacy.
Uncheck the option "Prevent cross-site tracking"
Restart the browser and try logging in again.
In Google Chrome:
Click on the 3 dots to access the settings menu in the top right corner.
Select Settings from the drop down menu.
Under Privacy and Security select Cookies and other site data
Enable to option that states Send a "Do Not Track" request with your browsing traffic.
Refresh or close and reopen your browser for changes to occur.
Note: "Safari 13.1 contains an update that may cause issues with downloading files, chat alerts, and displaying images in Canvas. Canvas engineers are currently working on a solution for this issue. Until then, you can avoid errors with files and images by disabling cross-site tracking prevention in Safari when using Canvas."