Luminosity ratio of keyboard focus indicator on 'Places to buy' control is less than 3:1

Is it an issue related to Adaptive Cards?

Yes, this is related to Adaptive Card. However, it does not repro on Adaptive Cards Designer.

What is the PWD impact?

When the keyboard focus indicator on the “Places to buy” control has a luminosity contrast ratio less than 3:1, users with low vision or those in high‑contrast settings cannot reliably perceive where focus is.

What browsers and screen readers do this issue affect?

Windows: Edge with Windows Narrator

Are there any code-based customization done to Web Chat?

No, I am using Web Chat without any customizations except "styleOptions".

What version of Web Chat are you using?

Latest production

Which area does this issue affect?

Others or unrelated

What is the public URL for the website?

No response

How to reproduce the issue?

Repro Steps: ​

1. Open URL: Web Chat in edge browser.
2. Ask query 'Carousel'.
3. Navigate to Places to buy control.
4. Observe the issue that Luminosity ratio of keyboard focus indicator on 'Places to buy' control is less than 3:1

What do you expect?

Luminosity ratio of keyboard focus indicator on 'Places to buy' control should be equal or greater than 3:1

What actually happened?

Luminosity ratio of keyboard focus indicator on 'Places to buy' control is less than 3:1

Do you have any screenshots or recordings to repro the issue?

Did you find any DOM elements that might have caused the issue?

No response

MAS reference

No response

WCAG reference

https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast

WAI-ARIA reference

No response

Adaptive Card JSON

Additional context

No response

Reproduce the issue in Web Chat using Edge and the 'Carousel' query, then navigate to the 'Places to buy' control and inspect its keyboard focus indicator. Done means the indicator's luminosity contrast ratio is at least 3:1, including for the reported Windows Narrator scenario.