Switch states not visible in High Contrast Mode

Created by: softwarea

Bootstrap 4.6: The states of a simple switch are not visible in Windows High Contrast Mode.

I used the following code from the documentation and enabled the High Contrast Mode with [Left-Alt]+[Left-Shift]+[Print].

<div class="custom-control custom-switch">
  <input type="checkbox" class="custom-control-input" id="customSwitch1">
  <label class="custom-control-label" for="customSwitch1">Toggle this switch element</label>
</div>

The toggle indicator is not visible.

Here is a CodePen sample.

I believe this is a bug? Anybody knows a quick workaround?