Seeking idMso for TRANSFORM tab in Backstage in Word 365 v 1908

I have been searching everywhere for an answer to this rather easy question.

In Word 365 v 1908 there is a new tab in BackStage named TRANSFORM which opens Sway service.

I need to shut that off for our users, but can't find the idMso anywhere to reference the tab and hide it.

Anywhere this can be found?  Or does anyone know it already to post here?