As of Dublin, a change was made in the client-side processing code of UI Actions.
If you have a UI Action where the Action name contains a period (.), and the Action name is used in a gsftSubmit() call in the client-script portion of the script, it will throw this error: Uncaught SyntaxError: Unexpected token.
In your UI Actions, if you have an Action name that contains a period (.), replace it with an underscore (_).
Related Problem: PRB586664