It’s very likely this action is prevented as part of the browser’s security model.
Edit: indeed, testing right now in Safari, I get the error type property cannot be changed
.
Edit 2: that seems to be an error straight out of jQuery. Using the following straight DOM code works just fine:
var pass = document.createElement('input');
pass.type="password";
document.body.appendChild(pass);
pass.type="text";
pass.value="Password";
Edit 3: Straight from the jQuery source, this seems to be related to IE (and could either be a bug or part of their security model, but jQuery isn’t specific):
// We can't allow the type property to be changed (since it causes problems in IE)
if ( name == "type" && jQuery.nodeName( elem, "input" ) && elem.parentNode )
throw "type property can't be changed";