{
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            {
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      "constructor": {
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      "extends": {
        "__compat": {
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              {
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                "notes": "Strict mode is required."
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          "status": {
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        }
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      "private_class_fields": {
        "__compat": {
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          "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Classes/Private_properties",
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            "opera": "mirror",
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            },
            "safari_ios": "mirror",
            "samsunginternet_android": "mirror",
            "webview_android": "mirror",
            "webview_ios": "mirror"
          },
          "status": {
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            "standard_track": true,
            "deprecated": false
          }
        }
      },
      "private_class_methods": {
        "__compat": {
          "description": "Private class methods",
          "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Classes/Private_properties",
          "spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-lexical-grammar.html#prod-PrivateIdentifier",
          "support": {
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              "version_added": "84"
            },
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            "edge": "mirror",
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          },
          "status": {
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      "public_class_fields": {
        "__compat": {
          "description": "Public class fields",
          "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Classes/Public_class_fields",
          "spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-functions-and-classes.html#prod-FieldDefinition",
          "support": {
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              "version_added": "72"
            },
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            },
            "edge": "mirror",
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            },
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                "partial_implementation": true,
                "notes": "Parentheses in field initializers can lead to <code>ReferenceError</code>s. See <a href='https://webkit.org/b/236843'>bug 236843</a>."
              },
              {
                "version_added": "14",
                "version_removed": "14.1",
                "partial_implementation": true,
                "notes": "Doesn't support public static fields. See <a href='https://webkit.org/b/194095'>bug 194095</a>."
              }
            ],
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}