Blackboard's recommendations for browser: https://help.blackboard.com/Learn/Student/Ultra/Getting_Started/Browser_Support Blackboard browser checker: https://help.blackboard.com/Learn/Student/Ultra/Getting_Started/Browser_Support/Browser_Checker.
Our Blackboard system is upgraded monthly and browsers are also updated frequently so there is always a chance that one of the updates will cause an unexpected issue. We do recommend that you have more than one browser installed on your system in the event of a problem with any specific browser.