Feature summary (what you would like to be able to do and where):
During the development of my gadget utilizing Codex I'm meeting the requirements of "freezing" the whole dialog including disabling the close button, instead of just removing it which will cause layout shifts.
Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
To "freeze" the dialog, as said above.