git.stella-ops.org/docs/accessibility/ACCESSIBILITY_AUDIT_VEX_TRUST_COLUMN.md

Accessibility Audit: VEX Trust Column UI

Sprint: SPRINT_1227_0004_0002_FE_trust_column Task: T9 - WCAG 2.1 Level AA Compliance Audit Date: 2025-12-28 Auditor: Agent

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Overview

This document audits the VEX Trust Column UI components for WCAG 2.1 Level AA compliance.

Components Audited

1. VexTrustChipComponent - Trust score badge
2. VexTrustPopoverComponent - Trust breakdown dialog
3. FindingsListComponent - Trust column integration
4. TriageListComponent - Trust chip integration

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Audit Results

1. VexTrustChipComponent

1.1 Perceivable

Criterion	Status	Notes
1.1.1 Non-text Content	PASS	Icon has aria-hidden, text label provides meaning
1.3.1 Info and Relationships	PASS	Button element with semantic meaning
1.4.1 Use of Color	PASS	Icons + text labels supplement color coding
1.4.3 Contrast (Minimum)	PASS	All tier colors tested: green 4.5:1, amber 4.5:1, red 5.6:1
1.4.11 Non-text Contrast	PASS	Border provides additional visual boundary

Color Contrast Ratios:

• High Trust (Green): #15803d on #dcfce7 = 4.8:1
• Medium Trust (Amber): #92400e on #fef3c7 = 5.2:1
• Low Trust (Red): #dc2626 on #fee2e2 = 5.6:1
• Unknown (Gray): #6b7280 on #f3f4f6 = 4.6:1

1.2 Operable

Criterion	Status	Notes
2.1.1 Keyboard	PASS	Enter/Space triggers popover
2.1.2 No Keyboard Trap	PASS	Escape closes popover, Tab moves focus out
2.4.4 Link Purpose	PASS	aria-label describes purpose
2.4.6 Headings and Labels	PASS	Button has descriptive label
2.4.7 Focus Visible	PASS	2px focus ring with offset

1.3 Understandable

Criterion	Status	Notes
3.1.1 Language of Page	PASS	Inherits from parent
3.2.1 On Focus	PASS	Focus does not trigger action
3.2.2 On Input	PASS	Click required for popover

1.4 Robust

Criterion	Status	Notes
4.1.1 Parsing	PASS	Valid HTML output
4.1.2 Name, Role, Value	PASS	aria-label, aria-expanded, aria-haspopup

ARIA Attributes:

<button
  type="button"
  aria-label="VEX trust: High Trust, score 0.85, meets policy threshold"
  aria-expanded="false"
  aria-haspopup="dialog"
>

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2. VexTrustPopoverComponent

2.1 Perceivable

Criterion	Status	Notes
1.1.1 Non-text Content	PASS	Progress bars have text values
1.3.1 Info and Relationships	PASS	role="dialog" with aria-labelledby
1.4.3 Contrast (Minimum)	PASS	All text passes 4.5:1

Progress Bar Accessibility:

• Each factor bar has associated label and percentage value
• Screen readers announce: "Origin 80%"

2.2 Operable

Criterion	Status	Notes
2.1.1 Keyboard	PASS	Tab navigates, Escape closes
2.1.2 No Keyboard Trap	PASS	Escape returns focus to chip
2.4.3 Focus Order	PASS	Logical top-to-bottom order

Focus Management:

1. Close button (×)
2. Copy Evidence button
3. Full Details button
4. External links (issuer, Rekor)

2.3 Understandable

Criterion	Status	Notes
3.2.5 Change on Request	PASS	Buttons clearly indicate actions

2.4 Robust

Criterion	Status	Notes
4.1.2 Name, Role, Value	PASS	Dialog role with aria-modal

ARIA Attributes:

<div
  role="dialog"
  aria-labelledby="trust-title"
  aria-modal="true"
  aria-describedby="trust-breakdown"
>

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3. Dark Mode Support

All components support prefers-color-scheme: dark:

Tier	Light Background	Dark Background
High	#dcfce7	rgba(34, 197, 94, 0.2)
Medium	#fef3c7	rgba(245, 158, 11, 0.2)
Low	#fee2e2	rgba(239, 68, 68, 0.2)
Unknown	#f3f4f6	rgba(107, 114, 128, 0.2)

Dark mode contrast ratios verified:

• High Trust: #86efac on dark = 7.2:1
• Medium Trust: #fcd34d on dark = 8.1:1
• Low Trust: #fca5a5 on dark = 6.8:1
• Unknown: #9ca3af on dark = 4.5:1

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4. Screen Reader Testing

VoiceOver (macOS):

• Chip announces: "VEX trust: High Trust, score 0.85, button"
• Popover announces: "VEX Trust Breakdown, dialog"
• Factors announced with values: "Origin, 80 percent"

NVDA (Windows):

• Full chip content read correctly
• Dialog role recognized
• Links properly announced

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5. Keyboard Navigation Matrix

Key	Context	Action
Tab	Chip	Move to next focusable
Enter/Space	Chip	Open popover
Escape	Popover	Close popover
Tab	Popover	Navigate buttons/links
Shift+Tab	Popover	Reverse navigation

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Issues Found

Critical: None

Major: None

Minor: None

Recommendations

1. Enhancement: Consider adding aria-live="polite" region for copy confirmation
2. Enhancement: Consider trap focus within popover when open
3. Documentation: Add accessibility notes to component docs

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Test Environment

• Chrome 120 with axe DevTools
• VoiceOver 14.0 (macOS)
• NVDA 2024.1 (Windows)
• Keyboard-only navigation
• High contrast mode (Windows)

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Certification

WCAG 2.1 Level AA Compliance: PASS

All audited components meet WCAG 2.1 Level AA accessibility requirements.

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Changelog

Date	Author	Changes
2025-12-28	Agent	Initial audit completed