What is the width of scrollbar?
For Windows it usually varies between 12px and 20px . If the browser doesn't reserve any space for it (the scrollbar is half-translucent over the text, also happens), then it may be 0px .
How to change scrollbar width in CSS?
The scrollbar-width property is used to set the width or thickness of an element's scrollbar when shown. This property can be used on pages where the user interface requires the element to be displayed more prominently and shrinking the scrollbar width gives more space to the element.