PreValidate Plugin Error Message Display Behavior

I have a preValidate plugin running where I am trying to use the following code to display an error message to the user:

throw new InvalidPluginExecutionException("This Time Entry record has already been accepted and cannot be modified.");

When this throws, I get additional information in the popup such as "An error has occured in the <plugin name> Plugin. EX Message:" followed by the text as in the screenshot below:

What might I be missing if I only want the message to display? I only want the Business Process Error with the message/text I've specified in my code.