openclaw
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Multi-channel AI gateway with extensible messaging integrations
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# Accessibility Debugging Snippets
Use these JavaScript snippets with the `evaluate_script` tool.
## 1. Find Orphaned Form Inputs
Finds form inputs that lack an associated label (no `label[for]`, `aria-label`, `aria-labelledby`, or wrapping `<label>`).
```js
() =>
Array.from(document.querySelectorAll('input, select, textarea'))
.filter(i => {
const hasId = i.id && document.querySelector(`label[for="${i.id}"]`);
const hasAria =
i.getAttribute('aria-label') || i.getAttribute('aria-labelledby');
return !hasId && !hasAria && !i.closest('label');
})
.map(i => ({
tag: i.tagName,
id: i.id,
name: i.name,
placeholder: i.placeholder,
}));
```
## 2. Measure Tap Target Size
Returns the bounding box dimensions of an element. Pass the element's `uid` from the snapshot as an argument to `evaluate_script`.
```js
el => {
const rect = el.getBoundingClientRect();
return {width: rect.width, height: rect.height};
};
```
## 3. Check Color Contrast
Approximates the contrast ratio between an element's text color and background color. Pass the element's `uid` to test against WCAG AA (4.5:1 for normal text, 3:1 for large text).
**Note**: This uses a simplified algorithm and may not account for transparency, gradients, or background images. For production-grade auditing, consider injecting `axe-core`.
```js
el => {
function getRGB(colorStr) {
const match = colorStr.match(/rgba?\((\d+),\s*(\d+),\s*(\d+)/);
return match
? [parseInt(match[1]), parseInt(match[2]), parseInt(match[3])]
: [255, 255, 255];
}
function luminance(r, g, b) {
const a = [r, g, b].map(function (v) {
v /= 255;
return v <= 0.03928 ? v / 12.92 : Math.pow((v + 0.055) / 1.055, 2.4);
});
return a[0] * 0.2126 + a[1] * 0.7152 + a[2] * 0.0722;
}
const style = window.getComputedStyle(el);
const fg = getRGB(style.color);
let bg = getRGB(style.backgroundColor);
const l1 = luminance(fg[0], fg[1], fg[2]);
const l2 = luminance(bg[0], bg[1], bg[2]);
const ratio = (Math.max(l1, l2) + 0.05) / (Math.min(l1, l2) + 0.05);
return {
color: style.color,
bg: style.backgroundColor,
contrastRatio: ratio.toFixed(2),
};
};
```
## 4. Global Page Checks
Checks document-level accessibility settings often missed in component testing.
```js
() => ({
lang:
document.documentElement.lang ||
'MISSING - Screen readers need this for pronunciation',
title: document.title || 'MISSING - Required for context',
viewport:
document.querySelector('meta[name="viewport"]')?.content ||
'MISSING - Check for user-scalable=no (bad practice)',
reducedMotion: window.matchMedia('(prefers-reduced-motion: reduce)').matches
? 'Enabled'
: 'Disabled',
});
```