2nd/10_Wiki/Topic_Programming/Programming & Language/Interop 2025.md

---
id: wiki-2026-0508-interop-2025
title: Interop 2025
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Web Interop 2025]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [web-platform, browser, standards]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: HTML/CSS/JavaScript
  framework: Web Platform
---

# Interop 2025

## 매 한 줄
> **"매 browser vendor 들이 매년 합의하여 fix 하는 web platform inconsistency list"**. Apple, Google, Microsoft, Mozilla, Bocoup, Igalia 가 공동으로 select 한 focus area 를 1년간 implement, web-platform-tests pass rate 의 dashboard 로 progress 의 track. 2025 cycle 의 anchor positioning, scrollbar styling, navigation API, View Transitions cross-document, storage access API 가 highlight.

## 매 핵심

### 매 origin & process
- 2021 Compat 2021 시작, 2022 부터 "Interop" 명칭.
- 매년 vendor 공동 선정 + community proposal.
- WPT (web-platform-tests) score 로 measure — wpt.fyi dashboard.

### 매 Interop 2025 의 focus areas
- **Anchor positioning** (CSS): tooltip/popover 의 declarative anchor.
- **View Transitions cross-document**: MPA 도 SPA 같은 transition.
- **Scrollbar gutter / colors**: scrollbar styling cross-browser.
- **Navigation API**: history API replacement.
- **Storage Access API**: cross-site cookie consent flow.
- **Container queries** (residual gaps).
- **Custom highlights API**: native highlight rendering.

### 매 응용
1. Web feature 의 production-safe baseline 결정 (Baseline initiative 와 align).
2. Polyfill / progressive enhancement strategy 의 기준.
3. Browser team 의 quarterly priority.

## 💻 패턴

### Anchor positioning (CSS)
```css
/* Trigger */
.btn { anchor-name: --my-anchor; }

/* Popover positioned relative to anchor */
.tooltip {
  position: absolute;
  position-anchor: --my-anchor;
  top: anchor(bottom);
  left: anchor(center);
  translate: -50% 8px;
}
```

### View Transitions cross-document
```html
<!-- both pages opt in -->
<meta name="view-transition" content="same-origin">
<style>
  @view-transition { navigation: auto; }
  .hero { view-transition-name: hero; }
</style>
```

### Navigation API
```javascript
navigation.addEventListener('navigate', (e) => {
  if (!e.canIntercept || e.hashChange) return
  e.intercept({
    handler: async () => {
      const data = await fetch(e.destination.url).then(r => r.json())
      render(data)
    },
  })
})
```

### Storage Access API
```javascript
// inside iframe — request 1P-like cookie access
if (await document.hasStorageAccess() === false) {
  try {
    await document.requestStorageAccess()
  } catch (e) { /* user denied */ }
}
```

### Scrollbar styling (modern)
```css
.list {
  scrollbar-gutter: stable both-edges;
  scrollbar-width: thin;
  scrollbar-color: var(--thumb) transparent;
}
```

### Feature detect via Baseline / `@supports`
```css
@supports (anchor-name: --x) {
  .tooltip { position-anchor: --my-anchor; }
}
@supports not (anchor-name: --x) {
  .tooltip { /* fallback positioning JS */ }
}
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| New feature production use | Interop 2025 list + Baseline check |
| 필요한 feature 가 still red | polyfill or feature flag |
| Cross-browser bug found | wpt.fyi 에 issue file |
| Greenfield SPA | Navigation API 채택 검토 |
| Tooltip / popover | Anchor positioning + popover API |

**기본값**: 매 Baseline Newly Available + Interop 2025 통과 feature 만 의 default 사용.

## 🔗 Graph
- 변형: [[Interop 2026]]
- 응용: [[View Transitions API]] · [[Navigation API]]
- Adjacent: [[Chromium]] · [[Baseline]]

## 🤖 LLM 활용
**언제**: 매 web platform feature 의 cross-browser readiness 의 query, polyfill strategy, modern CSS/JS adoption 결정.
**언제 X**: server-side, native, non-browser runtime.

## ❌ 안티패턴
- **Single-vendor preview 의 production**: Chrome canary 만 의 working ≠ ship-ready.
- **WPT pass = bug-free 의 가정**: real-world edge case 는 WPT 가 다 cover X.
- **Polyfill 의 무지성 적용**: native 가 ship 된 후에도 polyfill 유지 = bundle bloat.
- **Interop list 의 구속**: list 외 의 feature 도 needed 면 채택 가능 — list 는 priority 일 뿐.

## 🧪 검증 / 중복
- Verified (web.dev/interop-2025, wpt.fyi/interop-2025, vendor blog posts 2025).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — Interop 2025 focus areas + adoption patterns |