I’ve never liked the style of the selected areas on the preview of a
broadcast message. They were a compromise, taking what’s on the map page
and giving it a shaded background so it looks less like a text box.
The trouble is all these stroked elements jumbled together made the page
look very busy. I think it can be a bit calmer if they look more like
the ‘tag’ component[1] from the Design System, which only uses shading.
Going for black text not blue, because it’s one less piece of visual
differentiation – again, trying to keep the busyness level down.
1. https://design-system.service.gov.uk/components/tag/
3c7364408b