If you have text in a text prompt and need to remove it you can't just delete all the text, you need to have something in there or it will not save. This has been an issue for as long as I remember but I've worked around it by just using a single space instead of deleting it.  This is annoying and trips new employees (and me) up so it would be nice to remedy at some point. 

Here is a good example of what I'm talking about: