Click on a test suite's three-dot menu from the Test Directory and select Duplicate.
Go to Tests > Test Suites.
Click on the three-dot menu of the test suite you would like to duplicate. It is found at the rightmost column and shows upon hovering.
Alternatively, you could click on the check box then click on Duplicate in the toolbar that appears. You can select more than one test suite using this method.
Click on Duplicate.
A toast notification confirms that you've duplicated your test suite.