Hi Craig,
This should be done out of the box; the exact message will depend on the
browser, for instance, on Safari you would be getting something like:
leave.png <
http://discuss.orbeon.com/file/t119778/leave.png>
Are you not seeing something like this? If not, is this for a form you
created with Form Builder? And what version of Orbeon Forms are you running?
‑Alex
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