Assertion:
Using a READONLY attribute in IE4 and IE5 on this element still allows a user to invoke the file...open dialog (from the "Browse..." button), although the text field is not directly editable. In IE5.5 plus, both the text field AND the file...open dialog are not usable.

Plain Input Type=File field, no READONLY attribute:
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Input Type=File field, READONLY attribute present.
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