For this simple code
{Dynamic@Rotate[Slider[Dynamic@x, {0, 2*Pi}], x],
Slider[Dynamic@x, {0, 2*Pi}]}
At x=0
the slider has an style like this
However if I drag the second slider a little, the style of the first slider change at the moment it started to rotate, like this
Moreover, the first slider isn't working normally. It's supposed to control its own rotation, but dragging doesn't work. The only way to move is to click on the bar, instead of dragging, which is weird for a slider. Why?
{Dynamic@Rotate[Slider[Dynamic@y, {0, 2*Pi}], x], Slider[Dynamic@x, {0, 2*Pi}]}
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