An action block that awaits a user assist request.
The fiber will pause until assistance has been requested.
An assist request is made by swiping up from the home button, it’s usually handled by Google search.
Note! Since Android 6, the app for “Now on Tap” (long-press on the home button) has to be selected as “Assist app” in System settings, Apps, Advanced (gear menu), Default Apps, Assist & voice input.