[Accessibility]MAS 1.4.11: The color contrast of the focus dot line on each selection items for LitView/CheckedListBox is below 3:1

[Vino-Wang]

.NET Core Version:
.NET SDK 5.0.100-PREVIEW.4.20213.26 + Latest VS2019

Have you experienced this same bug with .NET Framework?:
Yes

Problem description:
On navigating to each row using arrow keys (down/up) the focus has a color contrast below 3:1. The ratio is 2.4:1. Low vision users will face difficulty in knowing that there is focus on the rows.
ListView

CheckedListBox

Expected behavior:
When the tab navigation is moved to each row the focus on them should be at a ratio of 3:1 or greater than 3:1.

Minimal repro:

1. Open the attached project, build and run it.
   Non_Text_Contrast_for_focus_dotline.zip
2. Select one row of ListView or one item of checkedBoxList.
3. Launch the Accessibility Insights for windows tool, and open the Color Contrast analyzer.
4. Select the color of the focus dot line.

[Jessie-Zhang01]

#3322 tracks the overall support.

[SergeySmirnov-Akvelon]

Hi, @merriemcgaw. Do we really need to change the color of the focus rectangle? In a normal situation, this rectangle is so small that even a person without vision problems is hard to consider its color by default. If the color should be changed, then what color should we use? I think this color should be at a ratio of 3:1 or greater than 3:1. for blue and white colors at once

[merriemcgaw]

Great questions @SergeySmirnov-Akvelon , I'm going to take a look at the requirements and talk with @guybark about the requirements around contrast of the CheckedListBox.

[merriemcgaw]

After discussion with our Accessibility SME we need to do something here to indicate that the item is selected. @SergeySmirnov-Akvelon - is this something that we pick up from CommonControls or is it something that we would be able to reasonably adjust on our end. If we can't make the adjustment, then we can file a bug against Windows to help us out here.