Problem/Motivation
This is a followup to #1741498-39: Add a mobile preview bar to Drupal core.
After selecting a preview from the list, the selected device isn't marked as 'active'
Proposed resolution
Visually indicate which device preview is active.
Maybe we need a label in the preview UI as well, since the dropdown disappears when the user mouses away.
Remaining tasks
- Design
- Propose a patch
User interface changes
The active device in the preview will be indicated.
API changes
None