---
title: "Hardcoded `id` on an SVG `<filter>`, gradient, `<clipPath>` or `<mask>` inside a reusable component (lint/svg-global-id)"
description: "lint/svg-global-id: Ids are document-global. Generate the id with `useId()` (strip the colons for `url()`), or hoist one shared definition to the layout and…"
canonical: https://void-design.vercel.app/rules/lint/svg-global-id
lastModified: 2026-09-16
---

# Hardcoded `id` on an SVG `<filter>`, gradient, `<clipPath>` or `<mask>` inside a reusable component

`lint/svg-global-id` · severity **warn** · category Lint · detected by `void lint` and `void audit`

## Why it matters

Ids are document-global. Two instances (or any other SVG using `#filter`/`#gradient`) resolve `url(#…)` to whichever element came first, so the second instance silently renders with the wrong filter or none (Aceternity spotlight uses `id="filter"`).

## How to fix it

Generate the id with `useId()` (strip the colons for `url()`), or hoist one shared definition to the layout and reference it.

## Example

```tsx
const id = useId().replace(/:/g, '');
<filter id={`${id}-blur`}>…</filter>
<g filter={`url(#${id}-blur)`} />
```

## References

- https://react.dev/reference/react/useId

## More lint rules

`void lint` reports 67 rules in this category. Static source checks with no browser: Tailwind v4 silent failures, Next.js 16 API traps, React render-body bugs, accessibility markup, SEO files and motion hygiene.

- `animate-undefined` `animate-*` class with no matching `--animate-*` theme variable or `@keyframes` — [lint/animate-undefined](https://void-design.vercel.app/rules/lint/animate-undefined)
- `random-in-render` `Math.random()` / `Date.now()` / `new Date()` evaluated in a component render body — [lint/random-in-render](https://void-design.vercel.app/rules/lint/random-in-render)
- `duplicate-children-not-hidden` Children repeated for a marquee/loop without `aria-hidden` or `inert` on the copies — [lint/duplicate-children-not-hidden](https://void-design.vercel.app/rules/lint/duplicate-children-not-hidden)
- `conditional-hook` Hook called inside a JSX expression, `&&`, ternary or callback — [lint/conditional-hook](https://void-design.vercel.app/rules/lint/conditional-hook)
- `allocation-per-frame` `new Intl.NumberFormat` / `Intl.NumberFormat(` / `new Color(` inside an animation-frame callback — [lint/allocation-per-frame](https://void-design.vercel.app/rules/lint/allocation-per-frame)
- `setstate-per-pointer-move` React state set inside a `mousemove` / `pointermove` / `scroll` handler — [lint/setstate-per-pointer-move](https://void-design.vercel.app/rules/lint/setstate-per-pointer-move)
- `hardcoded-device-pixel-ratio` Canvas/WebGL renders with a literal `devicePixelRatio: 2` (or `width * 2`) — [lint/hardcoded-device-pixel-ratio](https://void-design.vercel.app/rules/lint/hardcoded-device-pixel-ratio)
- `button-missing-type` `<button>` (or `as="button"` default) without an explicit `type` — [lint/button-missing-type](https://void-design.vercel.app/rules/lint/button-missing-type)

Detected by `void lint` and `void audit`. Explain it in a terminal: `void rules lint/svg-global-id`