FileMaker Pro 15.0.1 (Advanced)
Create a new solution. Define one field 'MyField' (text, used as container for placeholder variable)
In layout mode create a new popover button. Display the fields contents as name: <<MyFieldname>>.
Check in browse mode: new record, enter some text in MyField, see the contents displayed as Name for Popover button.
Back to Layout Mode, copy and paste the popover button. No further action!
Switch to Browse mode, see the copy not display any popover.
Foto Layout mode to check what's wrong - and crash!
No workarround. When a copy is made from a popover button with placeholder text as its name, the copied is object is corrupted (i.e. invalid xml) and wherever the object is pasted it will cause the application to crash whenever it is touched in layout mode.