The Details view has an install button, but it only works if the wallpaper doesn't have multiple versions (e.g. different sizes available).  

Reproducible: Always

Steps to Reproduce:
1. Right-click desktop, click settings
2. Click "Get New Wallpapers..."
3. In Search box, enter "strange nature 5"
(This is only an example - any wallpaper with multiple versions/sizes will do.)
4. In the results list, click "Details".
5. Click the Install button.  A drop down list appears.  Click any size.
Actual Results:  
Nothing happens.

Expected Results:  
Wallpaper should be installed.