Hi,
I’ll try to expose my use case and why I think it could be convenient to have “hidden widget”.
I manage my professional notes and tasks in Grist. Tasks belong to Projects. Projects belong to Mission.
I have as many pages as I have missions. These pages (red rectangle on the screenshot) are all build on the same “model” (same widgets).
I used to set a filter on the project table (green arrow) to only shows projets corresponding to the mission. But doing this, I was not able to add a new project into this table which belongs to the proper mission.
So to solve this problem, I added a new widget (blue arrow) which is the selector for the projects table. So now, when I add a new project, it belongs to the proper mission. The thing is that “Mission” widget is not really useful on screen. It takes some place, and I never have to modify it. It can be (should be?) hidden.
That’s my point: it can be useful to hide such a widget. Or to have an option to set a selector (here, for the “Projects” table) which takes no place on the screen.
I hope I’m clear!
Thanks 
