Hi,
I noticed that, from version 0.32.0 to 0.33.0 of dash-core-components, one element of the slider, namely the blue rail, is set to visible by default.
Therefore, when hiding the slider using visibility:hidden CSS attribute in the layout, the rail remains visible:
Notice that parent div that is associated to a dcc.RangeSlider has visibility set to hidden while its children rc-slider-track and rc-slider-track1 has visibility: visible.
Note that I didn’t try for a standard Slider.
Cheers