In WebKit driven browsers, e.g. Safari, Chrome, borders with their style declared as dotted
are rendered with square dots instead of round.
Is there any way
A natively supported solution is currently lacking, as the specification does not define these properties explicitly, and leaves it for the browser's implementation.
You may, however, use SVG to create the border, as it offers full control over the characteristics you're after.
Draw a line, than define its stroke-dasharray
and stroke-linecap
attributes to achieve the desired effect.