Prerequisites

• I have searched for duplicate or closed feature requests
• I have read the contributing guidelines

Proposal

In form validation, when using:

<div class="valid-feedback">Looks good!</div>

The feedback is visually hidden but still accessible to ATs users thanks to:

.valid-feedback, .visually-hidden, .visually-hidden-focusable:not(:focus):not(:focus-within) {
    position: absolute!important;
    width: 1px!important;
    height: 1px!important;
    padding: 0!important;
    margin: -1px!important;
    overflow: hidden!important;
    clip: rect(0,0,0,0)!important;
    white-space: nowrap!important;
    border: 0!important;
}

But there is also a

.valid-feedback {
    display: none;
}

rule coming from:

  @if $state == "valid" {
    .#{$state}-feedback {
      display: none;
      @extend .visually-hidden; // Boosted mod: Do not visually display .valid-feedback
    }

in scss\mixins\_forms.scss

The problem is that using display: none; will also prevent it to be rendered by the ATs.

When a field is valid, we only have:

So we have a visual feedback but it's not accessible for ATs.
It means actually when using Boosted, ATs can't explicitly stated that a field is valid.

Motivation and context

The good part is that, if we apply some actions spotted during the DevTestDays preparation and especially In Docs / Forms / Validation, No programmatic link between error messages dans input fields #37405, a valid field can be implicytly stated as valid because of not being explicitly stated as invalid.

=> for a valid preview, see https://deploy-preview-1559--boosted.netlify.app/docs/5.2/examples/form/ in Add form example in boosted doc #1559

The question is what should we do while waiting the opinion of Boostrap regarding the issue opened by @Aniort?

Some options:
Made the changes only in Boosted?
Remove the display: none; rule?
Start using aria-invalid="<true | false>" in Boosted forms to provide a feedback?