Color selection preview

[spudthebud]

Here's a user story to demonstrate the feature request:

User story:
I am sighted and use NVDA to debug accessibility problems. Focus highlight helps me as my non-visual skills aren't as developed my blind peers. I am in the NVDA settings at the Focus Highlight list item. I can set color values by RGB codes. When in "focus in focus mode" grouping and in color edit, I set the value to FFFF00. However, I have no idea what color that is going to display on the screen. I have to go to a webpage that lets me enter RGB values so I can see a preview.

It would be helpful if there was a patch next to the color edit in the settings that showed a preview of the color. This is a common pattern in visual interfaces where color selection is a task.