I have a 2013 workflow that creates a sub-site when a new item is added to a specific list. This was working beautifully until today. Now, whenever a new item is added to the list, the item is added and then the webpage hangs, seemingly stuck before the workflow is started. There is no error. There is no entry in either the Workflow History or Workflow Tasks list. No helpful information in the ULS logs or event viewer.
What happened and how can I get it back up and running?