The problem is that new value is writen into text
field and text field dismiss. But after
that jelly wants to commit new value by "Enter"
key pushing on non-existing text field and that is
why it fails.
Workaround is to call
JellyProperties.setFast(false); because it happens
only in fast mode.

Possible fix is to remove
jTextComponent.transferFocus() in JamTextComponent
at line 39. What do think Steve?

Test case to reproduce:

        String path = "Editing|Editor
Settings|Java Editor";
        Options.show();
        Options opt = new Options();
        PropertiesWindow pw =
opt.getPropertiesWindow(path, false);
        pw.switchToPropertiesTab();
        pw.setText("Font Size","13");