This is already modifiable in about:config "mousewheel.min_line_scroll_amount"
there is absolutely no reason this should not be an option settings
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Scrolling is always the thing that puts me off Firefox, compared to the Edge and Chrome (any other modern browser) the scrolling feels incredibly slow and janky.
The thing is you can achieve really nice scrolling with the msdPhysics options, but its a pain to setup and does not sync across to other computers. Just easier to use Edge.