Please increase the zoom level of your Safari to 100% or higher, to see if the items could be shown. To learn how to increase zoom level, please refer to: Change the font size or zoom level of web pages in Safari
If the issue still could not be resolved, please use another supported browser (e.g. Chrome, Firefox) to access Blackboard. You can check Blackboard Help: Browser Support, and make use of Blackboard Help: Browser Checker as well.