have you tried remove all cl-container extension from QMC (enterprise) or from the extension folder (desktop). Restart to check if the extension can still be dragged in. If can't then good, it is properly removed.
Download the file again and install it to test. If still cannot, open up the browser developer console and check for error messages.
~ By Candice. Superb experience and enthusiasm on Tableau, Qlik Sense and Power BI. Visit https://datamakery.com for continuous learning program on analytics.