cssClasses - how to use, and is it even supported?

[smileBeda]

Here it is said that cssClasses is an option but the option doc does not mention it, and no matter what I pass to the option, it always ends in undefined classes produced in the HTML.

I then found

noUiSlider/src/nouislider.ts

Line 4 in faa3252

target: string;

and if I pass all of those classes like :

cssClasses: {
    target: " string",
    base: " string",
    origin: " string",
    handle: " string",
    handleLower: " string",
    handleUpper: " string",
    touchArea: " string",
    horizontal: " string",
    vertical: " string",
    background: " string",
    connect: " string",
    connects: " string",
    ltr: " string",
    rtl: " string",
    textDirectionLtr: " string",
    textDirectionRtl: " string",
    draggable: " string",
    drag: " string",
    tap: " string",
    active: " string",
    tooltip: " string",
    pips: " string",
    pipsHorizontal: " string",
    pipsVertical: " string",
    marker: " string",
    markerHorizontal: " string",
    markerVertical: " string",
    markerNormal: " string",
    markerLarge: " string",
    markerSub: " string",
    value: " string",
    valueHorizontal: " string",
    valueVertical: " string",
    valueNormal: " string",
    valueLarge: " string",
    valueSub: " string",
}

well... it produces HTML elements with noUi- string, which makes absolutely no sense to me. it seems to replace the class rather than append, and only works if we overwrite them all?
Indeed, I can then also overwrite that with cssPrefix: '', but... that fully defies the purpose of this, IMO.

The final goal is to add classes from Bootstrap - and that just becomes impossible, if we have to either remove the noUi prefix just to add something like a bg-danger (thus totally breaking noUI) or append to it, therefore breaking Bootstrap.

Is there any solution to this?