Why only horizontal sliders, and not vertical ones?
And would it be possible to have resizable widgets, so they can ft in a smartphone screen?
Thank you!
you can resize by clicking at right bottom corner and dragging to desired size.
because it easy to use a horizontal and looks better 
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easy and looks better ? That’s your advice: if you want to put several sliders side by side they would look better if vertical.
Thanks for the info about how to resize. But, they come at minimum size : what if I want them smaller? For instance, I’d like to put 3 sliders side by side to adjust the color of a LED strip and display the widgets on a smartphone. But the sliders minimum size is quite large, whith some empty space, so they could be smaller…