CSS display: contents

`display: contents` causes an element's children to appear as if they were direct children of the element's parent, ignoring the element itself. This can be useful when a wrapper element should be ignored when using CSS grid or similar layout techniques.

:has() CSS relational pseudo-class

Select elements containing specific content. For example, `a:has(img)` selects all `<a>` elements that contain an `<img>` child.

selector list argument of :nth-child and :nth-last-child CSS pseudo-classes

The newest versions of `:nth-child()` and `:nth-last-child()` accept an optional `of S` clause which filters the children to only those which match the selector list `S`. For example, `:nth-child(1 of .foo)` selects the first child among the children that have the `foo` class (ignoring any non-`foo` children which precede that child). Similar to `:nth-of-type`, but for arbitrary selectors instead of only type selectors.

Element.insertAdjacentElement() & Element.insertAdjacentText()

Methods for inserting an element or text before or after a given element, or appending or prepending an element or text to a given element's list of children.

documentfragment api: children

documentfragment api: replacechildren

document api: children

document api: replacechildren

element api: children

element api: replacechildren

notrestoredreasons api: children

selection api: selectallchildren

css property: position: absolutely-positioned flex children