Nested pseudo elements styling (::before::marker or ::after::marker)

[danielsakhapov]

• Specification title: Nested pseudo elements styling (::before::marker or ::after::marker)
• Specification or proposal URL (if available): https://www.w3.org/TR/css-pseudo-4/#marker-pseudo
• WebKit standards-position: Nested pseudo elements styling (::before::marker or ::after::marker) WebKit/standards-positions#425

Other information

In addition to styling {::before/::after}::marker, support for nested pseudo elements styling is essential for ::column::scroll-marker styling, which has been resolved for css-overflow-5.

WPT test for ::before::marker styling