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Shadow DOM (V1)

- WD

Method of establishing and maintaining functional boundaries between DOM trees and how these trees interact with each other within a document, thus enabling better functional encapsulation within the DOM & CSS.

Chrome

  1. ❌ 4 - 52: Not supported
  2. ✅ 53 - 134: Supported
  3. ✅ 135: Supported
  4. ✅ 136 - 138: Supported

Edge

  1. ❌ 12 - 18: Not supported
  2. ✅ 79 - 134: Supported
  3. ✅ 135: Supported

Safari

  1. ❌ 3.1 - 9.1: Not supported
  2. ✅ 10 - 18.3: Supported
  3. ✅ 18.4: Supported
  4. ✅ 18.5 - TP: Supported

Firefox

  1. ❌ 2 - 57: Not supported
  2. ❌ 58: Disabled by default
  3. ❌ 59 - 62: Disabled by default
  4. ✅ 63 - 136: Supported
  5. ✅ 137: Supported
  6. ✅ 138 - 140: Supported

Opera

  1. ❌ 9 - 39: Not supported
  2. ✅ 40 - 116: Supported
  3. ✅ 117: Supported

IE

  1. ❌ 5.5 - 10: Not supported
  2. ❌ 11: Not supported

Chrome for Android

  1. ✅ 135: Supported

Safari on iOS

  1. ❌ 3.2 - 9.3: Not supported
  2. ◐ 10 - 10.3: Partial support
  3. ✅ 11 - 18.3: Supported
  4. ✅ 18.4: Supported
  5. ✅ 18.5: Supported

Samsung Internet

  1. ❌ 4: Not supported
  2. ◐ 5: Partial support
  3. ✅ 6.2 - 26: Supported
  4. ✅ 27: Supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10 - 12.1: Not supported
  2. ✅ 80: Supported

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported
  2. ✅ 135: Supported

Firefox for Android

  1. ✅ 137: Supported

QQ Browser

  1. ✅ 14.9: Supported

Baidu Browser

  1. ✅ 13.52: Supported

KaiOS Browser

  1. ❌ 2.5: Not supported
  2. ✅ 3: Supported
Resources:
Safari implementation bug
Firefox implementation bug
Google Developers - Shadow DOM v1: self-contained web components