A (proprietary) HTML attribute I'm keen to add to links is `modal`. I'll let you set this to "overlay", "aside", "above", "below", "leftside", "rightside", "aside", "top", "left", "bottom", or "right" to present the linked page as a modal dialog in the specified location. In relation to the link or not.
Mostly as a concession in my fight against overlays! Which are annoying us all.
@dean Yes, everything I implement in my browser engines will be fully accessible whatever that means for the I/O medium I'm targetting...
In the dominant browsers, implementing <dialog> with full accessibility is considered a priority by them...