2.2.7 [SVG11] Section 14.3.3, The 'overflow' and 'clip' properties
• The initial value for 'overflow' as defined in [CSS2-overflow] is 'visible'; however, SVG's user agent style sheet overrides this initial value and set the 'overflow' property on elements that establish new viewports (e.g., 'svg' elements), 'pattern' elements and 'marker' elements to the value 'hidden'.
IE9 Mode, IE10 Mode, IE11 Mode, and EdgeHTML Mode (All Versions)
On the outermost svg element that is inline in HTML5,
the initial value for the overflow property is