(I assume that this is a general-case bug, but I can try to track down further, if necessary.)
I have added a form button and changed the Action to “Link to screen”. If I select a Title value from the list of fields (i.e., “dynamic”), the actual title rendered is null. The only way I can get a Title to render is to select custom and type in a value (i.e., “static”).
We’ll fix it. Thank you for reporting!