How to set uxml template button to disabled within uxml as starting state?

I have been unable to figure out how to set a button as disabled within the uxml.

I’ve tried:

<ui:Button text="Save" display-tooltip-when-elided="true" name="optionsSaveBut" class="button" enabled="false"/>

But it seems it doesn’t work.

You have to do it by code by calling SetEnabled(false), not on the UXML.

It would be nice to be able to do it directly on UXML