Look at my screenshot (sorry, without a cursor). For my test border sensitivity width is not less than 4 pixels (may be 5). Is this width is not enough for you? May be for touchpad is not so good as for mouse. What was the border width when you use Cinnamon? May be this is really problem for some people, but on my side I see no problem (and I have not very good eyes).
Look at my screenshot (sorry, without a cursor). For my test border sensitivity width is not less than 4 pixels (may be 5). Is this width is not enough for you? May be for touchpad is not so good as for mouse. What was the border width when you use Cinnamon? May be this is really problem for some people, but on my side I see no problem (and I have not very good eyes).