<Slider ... style={{ width: '50%' }}/>
Result:

From chrome devtools:

It's seems that the second width: 50% is not intended to work this way. If it should have the same width as the root, just copying it this way leads to this bug, when the value is relative.
Result:

From chrome devtools:

It's seems that the second
width: 50%is not intended to work this way. If it should have the same width as the root, just copying it this way leads to this bug, when the value is relative.