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                    {
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                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "46",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                }
              ],
              "firefox_android": [
                {
                  "version_added": "57",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "46",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                }
              ],
              "ie": {
                "version_added": false
              },
              "nodejs": {
                "version_added": "8.10.0"
              },
              "opera": {
                "version_added": false
              },
              "opera_android": {
                "version_added": false
              },
              "safari": {
                "version_added": "10.1",
                "version_removed": "11.1"
              },
              "safari_ios": {
                "version_added": "10.3",
                "version_removed": "11.3"
              },
              "samsunginternet_android": {
                "version_added": false,
                "notes": "Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              },
              "webview_android": {
                "version_added": "60",
                "version_removed": "63",
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              }
            },
            "status": {
              "experimental": false,
              "standard_track": true,
              "deprecated": false
            }
          }
        },
        "wait": {
          "__compat": {
            "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Atomics/wait",
            "spec_url": "https://tc39.es/ecma262/#sec-atomics.wait",
            "support": {
              "chrome": [
                {
                  "version_added": "68"
                },
                {
                  "version_added": "60",
                  "version_removed": "63",
                  "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This was a temporary removal while mitigations were put in place."
                }
              ],
              "chrome_android": {
                "version_added": "60",
                "version_removed": "63",
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              },
              "edge": [
                {
                  "version_added": "79"
                },
                {
                  "version_added": "16",
                  "version_removed": "17",
                  "notes": "Support was removed to mitigate <a href='https://blogs.windows.com/msedgedev/2018/01/03/speculative-execution-mitigations-microsoft-edge-internet-explorer'>speculative execution side-channel attacks (Windows blog)</a>."
                }
              ],
              "firefox": [
                {
                  "version_added": "78"
                },
                {
                  "version_added": "57",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "48",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                },
                {
                  "version_added": "46",
                  "version_removed": "48",
                  "alternative_name": "futexWait",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "The method returns values <code>Atomics.OK</code>, <code>Atomics.TIMEDOUT</code>, and <code>Atomics.NOTEQUAL</code>, instead of the later-specified strings."
                }
              ],
              "firefox_android": [
                {
                  "version_added": "57",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "48",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                },
                {
                  "version_added": "46",
                  "version_removed": "48",
                  "alternative_name": "futexWait",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "The method returns values <code>Atomics.OK</code>, <code>Atomics.TIMEDOUT</code>, and <code>Atomics.NOTEQUAL</code>, instead of the later-specified strings."
                }
              ],
              "ie": {
                "version_added": false
              },
              "nodejs": {
                "version_added": "8.10.0"
              },
              "opera": {
                "version_added": false
              },
              "opera_android": {
                "version_added": false
              },
              "safari": {
                "version_added": "10.1",
                "version_removed": "11.1"
              },
              "safari_ios": {
                "version_added": "10.3",
                "version_removed": "11.3"
              },
              "samsunginternet_android": {
                "version_added": false,
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              },
              "webview_android": {
                "version_added": "60",
                "version_removed": "63",
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              }
            },
            "status": {
              "experimental": false,
              "standard_track": true,
              "deprecated": false
            }
          }
        },
        "xor": {
          "__compat": {
            "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Atomics/xor",
            "spec_url": "https://tc39.es/ecma262/#sec-atomics.xor",
            "support": {
              "chrome": [
                {
                  "version_added": "68"
                },
                {
                  "version_added": "60",
                  "version_removed": "63",
                  "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This was a temporary removal while mitigations were put in place."
                }
              ],
              "chrome_android": {
                "version_added": "60",
                "version_removed": "63",
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              },
              "edge": [
                {
                  "version_added": "79"
                },
                {
                  "version_added": "16",
                  "version_removed": "17",
                  "notes": "Support was removed to mitigate <a href='https://blogs.windows.com/msedgedev/2018/01/03/speculative-execution-mitigations-microsoft-edge-internet-explorer'>speculative execution side-channel attacks (Windows blog)</a>."
                }
              ],
              "firefox": [
                {
                  "version_added": "78"
                },
                {
                  "version_added": "57",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "46",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                }
              ],
              "firefox_android": [
                {
                  "version_added": "57",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ],
                  "notes": "Support was disabled by default to mitigate <a href='https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing-attack/'>speculative execution side-channel attacks (Mozilla Security Blog)</a>."
                },
                {
                  "version_added": "55",
                  "version_removed": "57"
                },
                {
                  "version_added": "46",
                  "version_removed": "55",
                  "flags": [
                    {
                      "type": "preference",
                      "name": "javascript.options.shared_memory",
                      "value_to_set": "true"
                    }
                  ]
                }
              ],
              "ie": {
                "version_added": false
              },
              "nodejs": {
                "version_added": "8.10.0"
              },
              "opera": {
                "version_added": false
              },
              "opera_android": {
                "version_added": false
              },
              "safari": {
                "version_added": "10.1",
                "version_removed": "11.1"
              },
              "safari_ios": {
                "version_added": "10.3",
                "version_removed": "11.3"
              },
              "samsunginternet_android": {
                "version_added": false,
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              },
              "webview_android": {
                "version_added": "60",
                "version_removed": "63",
                "notes": "Chrome disabled <code>SharedArrayBuffer</code> on January 5, 2018 to help reduce the efficacy of <a href='https://www.chromium.org/Home/chromium-security/ssca'>speculative side-channel attacks</a>. This is intended as a temporary measure until other mitigations are in place."
              }
            },
            "status": {
              "experimental": false,
              "standard_track": true,
              "deprecated": false
            }
          }
        }
      }
    }
  }
}