https://drafts.csswg.org/css-pseudo-4/#csspseudoelement Firefox is shipping support for ::marker in v68, including animation support. Safari supports it since v11 according to [caniuse](https://caniuse.com/#search=%3A%3Amarker).
https://drafts.csswg.org/css-pseudo-4/#csspseudoelement
Firefox is shipping support for ::marker in v68, including animation support.
Safari supports it since v11 according to caniuse.