If you're accessing your course from a mobile device or tablet or from within a small browser window, Blackboard will collapse the sidebar by default. To expand the sidebar, click the blue area to at the left side of the of the screen. If you don't see the blue area to expand the sidebar, try enlarging the browser window. You might also want to check that your browser window is not zoomed in as this will also cause Blackboard to hide the sidebar.
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