[CSS ::tooltip] Related `::tether` proposal for tooltip pointer/arrow

[Malvoz]

Regarding the Future idea Tooltip pointer/arrow:

A future consideration for ::tooltip is to add a way for authors to include a pointer/arrow with their tooltip that is associated with their ::tooltip psuedo.

This addition would require allowing sub-psuedo elements within ::tooltip. There would also need to be a way to know the position of the tooltip itself to position the arrow against, which can be accomplished with CSS Anchor Positioning.

As this ::tooltip proposal intends to utilize CSS Anchor Positioning to define the base positions I think the proposed ::tether pseudo-element should be noted.

[o-t-w]

Now that certain pseudo-elements can have their own pseudo-elements, perhaps ::tooltip can have a ::tether.

[alisonmaher]

This is a great callout, thanks for the feedback! I've updated the explainer to call out ::tether as something we could use as part of the proposal for the pointer/arrow addition.