diff --git a/src/cdk/stepper/step-header.ts b/src/cdk/stepper/step-header.ts
index f0709e3f9878..26ebcbbcb0f7 100644
--- a/src/cdk/stepper/step-header.ts
+++ b/src/cdk/stepper/step-header.ts
@@ -12,7 +12,7 @@ import {FocusableOption} from '../a11y';
 @Directive({
 selector: '[cdkStepHeader]',
 host: {
- 'role': 'tab',
+ 'role': 'button',
 },
 })
 export class CdkStepHeader implements FocusableOption {
diff --git a/src/material/stepper/step-header.ts b/src/material/stepper/step-header.ts
index eb95f01ad708..25c4ebd31b88 100644
--- a/src/material/stepper/step-header.ts
+++ b/src/material/stepper/step-header.ts
@@ -36,7 +36,7 @@ import {_CdkPrivateStyleLoader, _VisuallyHiddenLoader} from '@angular/cdk/privat
 'class': 'mat-step-header',
 '[class.mat-step-header-empty-label]': '_hasEmptyLabel()',
 '[class]': '"mat-" + (color || "primary")',
- 'role': 'tab',
+ 'role': 'button',
 },
 encapsulation: ViewEncapsulation.None,
 changeDetection: ChangeDetectionStrategy.OnPush,
diff --git a/src/material/stepper/stepper.html b/src/material/stepper/stepper.html
index 0f75e58c012b..d3fdb7b3cb73 100644
--- a/src/material/stepper/stepper.html
+++ b/src/material/stepper/stepper.html
@@ -11,7 +11,7 @@
 @switch (orientation) {
 @case ('horizontal') {
 <div>
- <div>
+ <div role="group">
 @for (step of steps; track step) {
 <ng-container [ngTemplateOutlet]="stepTemplate" @@ -22,12 +22,12 @@ } </div>
 
- <div>
+ <div role="group">
 @for (step of steps; track step) {
 <div #animatedContainer - role="tabpanel" + role="region" [id]="_getStepContentId($index)" [attr.aria-labelledby]="_getStepLabelId($index)" [class]="'mat-horizontal-stepper-content-' + _getAnimationDirection($index)" @@ -40,28 +40,30 @@ } @case ('vertical') { - @for (step of steps; track step) { - <div>
- <ng-container - [ngTemplateOutlet]="stepTemplate" - [ngTemplateOutletContext]="{step}"/>
- <div - #animatedContainer - - [class.mat-stepper-vertical-line]="!$last" - [class.mat-vertical-content-container-active]="selectedIndex === $index" - [attr.inert]="selectedIndex === $index ? null : ''">
- <div - role="tabpanel" - [id]="_getStepContentId($index)" - [attr.aria-labelledby]="_getStepLabelId($index)">
- <div>
- <ng-container [ngTemplateOutlet]="step.content"/>
+ <div role="group">
+ @for (step of steps; track step) {
+ <div>
+ <ng-container + [ngTemplateOutlet]="stepTemplate" + [ngTemplateOutletContext]="{step}"/>
+ <div + #animatedContainer + + [class.mat-stepper-vertical-line]="!$last" + [class.mat-vertical-content-container-active]="selectedIndex === $index" + [attr.inert]="selectedIndex === $index ? null : ''">
+ <div + role="region" + [id]="_getStepContentId($index)" + [attr.aria-labelledby]="_getStepLabelId($index)">
+ <div>
+ <ng-container [ngTemplateOutlet]="step.content"/>
+ </div>
 </div>
 </div>
 </div>
- </div>
- }
+ }
+ </div>
 }
 }
 
@@ -74,10 +76,7 @@
 (keydown)="_onKeydown($event)"
 [tabIndex]="_getFocusIndex() === step.index() ? 0 : -1"
 [id]="_getStepLabelId(step.index())"
- [attr.aria-posinset]="step.index() + 1"
- [attr.aria-setsize]="steps.length"
 [attr.aria-controls]="_getStepContentId(step.index())"
- [attr.aria-selected]="step.isSelected()"
 [attr.aria-label]="step.ariaLabel &#124;&#124; null"
 [attr.aria-labelledby]="(!step.ariaLabel && step.ariaLabelledby) ? step.ariaLabelledby : null"
 [attr.aria-disabled]="step.isNavigable() ? null : true"
diff --git a/src/material/stepper/stepper.ts b/src/material/stepper/stepper.ts
index 6d1399dae0df..69874b427378 100644
--- a/src/material/stepper/stepper.ts
+++ b/src/material/stepper/stepper.ts
@@ -131,7 +131,6 @@ export class MatStep extends CdkStep implements ErrorStateMatcher, AfterContentI
 '[class.mat-stepper-animating]': '_isAnimating()',
 '[style.--mat-stepper-animation-duration]': '_getAnimationDuration()',
 '[attr.aria-orientation]': 'orientation',
- 'role': 'tablist',
 },
 providers: [{provide: CdkStepper, useExisting: MatStepper}],
 encapsulation: ViewEncapsulation.None,
</div><div class="naked_ctrl">
<form action="/index.cgi/contrast" method="get" name="gate">
<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://patch-diff.githubusercontent.com/raw/angular/components/pull/31785.diff">(-&gt;オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="https://patch-diff.githubusercontent.com/raw/angular/components/pull/31785.diff" size="22" /></label> <label>モード: <select name="naked_post_mode">
<option value="default">デフォルト</option>
<option value="speech">音声ブラウザ</option>
<option value="ruby">ルビ付き</option>
<option value="contrast" selected="selected">配色反転</option>
<option value="larger-text">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>