Hey there 
It sounds like it might be a module error. I’d recommend opening the dev tools console (F12) and doing the drag to see if you have an error logged there. If there is an error, it might show you the name of a module which is causing the issue.
For a broader test, if the above doesn’t help you fix it, please check to see if it happens when you launch in safe configuration with all modules turned off.
Hope that helps!