Improve the presentation of the wallpaper portal
Testing with ASHPD, the wallpaper portal dialog looks like this:
I've never been entirely satisfied with the design of this one. It feels ambiguous - there's not much precedent to show a background permission dialog, the dialog doesn't explain itself, nor is the purpose of the visual content immediately obvious.
I've been playing around with some solutions and the best I've been able to come up with so far is this:
It presents itself as a preview, which is intended to communicate the purpose of the window. The bigger image is more useful as a preview, and it looks more like a preview too (just adding a top bar to the thumbnail again feels ambiguous).
The new design lives as part of the portals mockups.