Bar rest in long meters

Are we truly to be limited by this convention regarding bar rests in longer meters (such as 12/4 in the example below) where the rest is an upward rectangle. There are times (cadenzas for example, where a long meter and a hidden time signature), where a garden variety bar rest would be preferable, especially since we get those by default in unmeasured metre. I couldn’t find a setting, or a reference to this on the forum.
bar rest.jpg

You’re quite right that at present there is no option for this. We will look into adding an option to limit bar rests to a whole note (semibreve) in duration at some point in the future.