` with mouse events only - no keyboard, no ARIA *(diverges from all 4 systems)*
- Don't omit `aria-valuenow` updates during drag - AT users hear a stale value *(WAI-ARIA APG)*
- Don't let the visual thumb area be smaller than 12px with no hit-area expansion - fails WCAG 2.5.8 *(Material 3)*
- Don't use identical `aria-label` for both range thumbs *(WAI-ARIA APG)*
---
## Anti-patterns Cross-links
| Anti-pattern | Entry |
|--------------|-------|
| BAN-09 | Custom interactive widget with mouse events only, no keyboard - `reference/anti-patterns.md#ban-09` |
| BAN-11 | Touch target below 44px without padding expansion - `reference/anti-patterns.md#ban-11` |
---
## Benchmark Citations
| Claim | Sources |
|-------|---------|
| role="slider" + aria-valuenow/min/max required | WAI-ARIA APG Slider pattern |
| Arrow key step, Page key 10% step, Home/End to extremes | WAI-ARIA APG keyboard contract |
| 4px track height default | Material 3, Carbon |
| Thumb touch target ≥44px via pseudo-element | Material 3, Carbon accessibility guidelines |
| aria-valuetext for non-numeric human-readable values | WAI-ARIA APG, Radix Slider docs |
Full system URLs: `connections/design-corpora.md`
---
## Grep Signatures
```bash
# Slider thumb missing aria-valuenow (ARIA contract violation)
grep -rn 'role="slider"' src/ | grep -v 'aria-valuenow'
# Custom slider div with mouse events only — no keyboard handler
grep -rn 'class.*slider\|\.slider' src/ | grep 'onMouseDown\|mousedown' | grep -v 'onKeyDown\|keydown\|role="slider"'
# Thumb element potentially below 44px with no hit-area expansion
grep -rn '\.thumb\|slider-thumb' src/ | grep 'width:\s*[0-9]\{1,2\}px\|height:\s*[0-9]\{1,2\}px' | grep -v '::before\|::after\|padding'
# Range slider thumbs with identical aria-label
grep -rn 'role="slider"' src/ -A2 | grep 'aria-label' | sort | uniq -d
```
---
## Failing Example
```html
```
**Why it fails**: Not reachable by keyboard; no `role="slider"`; no `aria-valuenow`, `aria-valuemin`, or `aria-valuemax`; AT cannot read or change the value; touch users cannot interact via assistive touch.
**Grep detection**: `grep -rn '
` or add `role="slider"` + `aria-valuenow` + `aria-valuemin` + `aria-valuemax` + `aria-valuetext` + full keyboard event handlers (Arrow, Page, Home, End) to the thumb element.