[FEATURE] Slice Slider does not allow to set to desired value

[jadej02]

When using the slice slider, I wanted to select 118, and it would only allow me to select 117 or 119. I suggest allowing to adjust the slider by up and down keys or to type in the value manually.

[eric-unc]

Sorry for the late response to this, but you can increment or decrement by 1 if you click the ends of the slider. This is somewhat documented, if you hover over a slider. But still, there could be easier ways.

[eric-unc]

(Similar to #100 )