https://drafts.csswg.org/css-text-decor-4/#line-position Text decorations should not be inherited properties. Instead, they are applied to a parent "decorating box" and are rendered consistently through all children.
*** Bug 209070 has been marked as a duplicate of this bug. ***
<rdar://problem/73944239>
*** This bug has been marked as a duplicate of bug 167331 ***
.
*** This bug has been marked as a duplicate of bug 135353 ***