Seeing the same on Safari 15.5, is there a fix planned for this? Notably I do not see this issue in Safari Technology Preview.

+1, would also like to know if there's any plans to support this or the intent behind the lack of support.

Also curious to know why web extensions and app extensions have different permissions? The permissions in Safari for requested hosts are in ask mode by default after installing a web extension. By contrast, in Chrome and Firefox, web extensions permissions for requested sites are in allow mode.