The term "Visibility" is used to describe an object opacity (in the Settings panel -> Style), which is counterintuitive because in the Layers Panel we can toggle on/of the "Visibility" on an object for each responsive breakpoint.
The second problem is related to the fact that I can toggle the visibility of an object only from the Layers Panel, I should have these options in the Settings panel -> RWD settings also
1. Rename the "Visibility" term from the Settings panel -> Style to "Opacity".
2. Add the responsive visibility toggles in the Settings panel -> RWD settings (or similar)
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