I'm not 100% sold on whether this should be included in Popover or if it should be a feature specific thing, and I'm wondering if it should be part of MVP regardless since there are a lot of other things that are critical to this component's functionality. @lwatson @DTorsani-WMF what do you think? Are there any use cases coming up soon that will need this functionality, or is this more to support page previews and potential future projects?

The only use case I know that uses the images are link previews. Those are the most common use of a Popover, and obviously used everywhere there is a link on Wikipedia. I do feel that we should release an MVP that supports link previews entirely, but that support can be a more customizable layout thing and not specifically an image prop if that seems important.

@AnneT good point! We can allow users to adjust the height and width in the MVP. Page previews are the only case that uses images so I'm okay with removing image and layout support in the MVP considering that this use case was not requested or needed now.

As far as customizing the height of a Popover, this should be determined by its content plus padding. That being said, we should allow for setting of a max-height, especially on mobile. For width, there is a default width, min-width, and max-width provided.