Another feature of the completion list implementation we’re doing in SyntaxEditor for WPF is transparency.
When the completion list is displayed, you can hold down the Ctrl key and the completion list smoothly fades out to be mostly transparent. Releasing the Ctrl key fades the list back to be fully-opaque again.
|
 
A completion list displayed normally (left) and faded to be semi-transparent while the Ctrl key is held down (right)
|
The benefit of this feature is that the end user can quickly view the code covered up by the completion list if they need to.