Open your browser's dev tool and select the console view. In a course go to the participant page and add a participant. Click on the participant's role assignments and select a role. Click the cancel cross. Click again on the participant's role assignments and add the role again. Verify you don't see any errors in the console (you will without the patch applied) Verify you see the role displayed above the selector. Click the save icon Verify you see the role displayed above the selector still. Refresh the page.  Verify you see the role displayed above the selector still.