diff --git a/api/XMLHttpRequest.json b/api/XMLHttpRequest.json
index d0a555b3045820..31eb3e807e6295 100644
--- a/api/XMLHttpRequest.json
+++ b/api/XMLHttpRequest.json
@@ -157,7 +157,10 @@
         "__compat": {
           "description": "<code>abort</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/abort_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-abort",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-abort",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onabort"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -207,7 +210,10 @@
         "__compat": {
           "description": "<code>error</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/error_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-error",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-error",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onerror"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -407,7 +413,10 @@
         "__compat": {
           "description": "<code>load</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/load_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-load",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-load",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onload"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -425,7 +434,7 @@
               "version_added": "4"
             },
             "ie": {
-              "version_added": "10"
+              "version_added": "9"
             },
             "opera": {
               "version_added": "≤12.1"
@@ -457,7 +466,10 @@
         "__compat": {
           "description": "<code>loadend</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/loadend_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-loadend",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-loadend",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onloadend"
+          ],
           "support": {
             "chrome": {
               "version_added": "18"
@@ -493,7 +505,7 @@
               "version_added": "1.0"
             },
             "webview_android": {
-              "version_added": "≤37"
+              "version_added": "4.4"
             }
           },
           "status": {
@@ -507,7 +519,10 @@
         "__compat": {
           "description": "<code>loadstart</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/loadstart_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-loadstart",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-loadstart",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onloadstart"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -553,10 +568,10 @@
           }
         }
       },
-      "onreadystatechange": {
+      "open": {
         "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/onreadystatechange",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onreadystatechange",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open",
+          "spec_url": "https://xhr.spec.whatwg.org/#the-open()-method",
           "support": {
             "chrome": {
               "version_added": "1"
@@ -568,16 +583,18 @@
               "version_added": "12"
             },
             "firefox": {
-              "version_added": "1"
+              "version_added": "1",
+              "notes": "Starting in Firefox 30, synchronous requests on the main thread have been deprecated due to their negative impact on performance and the user experience. Therefore, the <code>async</code> parameter may not be <code>false</code> except in a <code>Worker</code>."
             },
             "firefox_android": {
-              "version_added": "4"
+              "version_added": "4",
+              "notes": "Starting in Firefox 30, synchronous requests on the main thread have been deprecated due to their negative impact on performance and the user experience. Therefore, the <code>async</code> parameter may not be <code>false</code> except in a <code>Worker</code>."
             },
             "ie": {
               "version_added": "5"
             },
             "opera": {
-              "version_added": "9"
+              "version_added": "8"
             },
             "opera_android": {
               "version_added": "10.1"
@@ -602,10 +619,10 @@
           }
         }
       },
-      "open": {
+      "overrideMimeType": {
         "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open",
-          "spec_url": "https://xhr.spec.whatwg.org/#the-open()-method",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/overrideMimeType",
+          "spec_url": "https://xhr.spec.whatwg.org/#the-overridemimetype()-method",
           "support": {
             "chrome": {
               "version_added": "1"
@@ -617,21 +634,25 @@
               "version_added": "12"
             },
             "firefox": {
-              "version_added": "1",
-              "notes": "Starting in Firefox 30, synchronous requests on the main thread have been deprecated due to their negative impact on performance and the user experience. Therefore, the <code>async</code> parameter may not be <code>false</code> except in a <code>Worker</code>."
+              "version_added": "1"
             },
             "firefox_android": {
-              "version_added": "4",
-              "notes": "Starting in Firefox 30, synchronous requests on the main thread have been deprecated due to their negative impact on performance and the user experience. Therefore, the <code>async</code> parameter may not be <code>false</code> except in a <code>Worker</code>."
-            },
-            "ie": {
-              "version_added": "5"
+              "version_added": "4"
             },
+            "ie": [
+              {
+                "version_added": "11"
+              },
+              {
+                "version_added": "5",
+                "notes": "Implemented via <code>ActiveXObject</code>"
+              }
+            ],
             "opera": {
-              "version_added": "8"
+              "version_added": "≤12.1"
             },
             "opera_android": {
-              "version_added": "10.1"
+              "version_added": "≤12.1"
             },
             "safari": {
               "version_added": "1.2"
@@ -653,10 +674,14 @@
           }
         }
       },
-      "overrideMimeType": {
+      "progress_event": {
         "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/overrideMimeType",
-          "spec_url": "https://xhr.spec.whatwg.org/#the-overridemimetype()-method",
+          "description": "<code>progress</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/progress_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-progress",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onprogress"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -673,15 +698,9 @@
             "firefox_android": {
               "version_added": "4"
             },
-            "ie": [
-              {
-                "version_added": "11"
-              },
-              {
-                "version_added": "5",
-                "notes": "Implemented via <code>ActiveXObject</code>"
-              }
-            ],
+            "ie": {
+              "version_added": "10"
+            },
             "opera": {
               "version_added": "≤12.1"
             },
@@ -689,7 +708,7 @@
               "version_added": "≤12.1"
             },
             "safari": {
-              "version_added": "1.2"
+              "version_added": "3"
             },
             "safari_ios": {
               "version_added": "1"
@@ -698,7 +717,7 @@
               "version_added": "1.0"
             },
             "webview_android": {
-              "version_added": "1"
+              "version_added": "≤37"
             }
           },
           "status": {
@@ -708,11 +727,10 @@
           }
         }
       },
-      "progress_event": {
+      "readyState": {
         "__compat": {
-          "description": "<code>progress</code> event",
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/progress_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-progress",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/readyState",
+          "spec_url": "https://xhr.spec.whatwg.org/#states",
           "support": {
             "chrome": {
               "version_added": "1"
@@ -730,16 +748,16 @@
               "version_added": "4"
             },
             "ie": {
-              "version_added": "10"
+              "version_added": "7"
             },
             "opera": {
-              "version_added": "≤12.1"
+              "version_added": "8"
             },
             "opera_android": {
-              "version_added": "≤12.1"
+              "version_added": "10.1"
             },
             "safari": {
-              "version_added": "3"
+              "version_added": "1.2"
             },
             "safari_ios": {
               "version_added": "1"
@@ -748,7 +766,7 @@
               "version_added": "1.0"
             },
             "webview_android": {
-              "version_added": "≤37"
+              "version_added": "1"
             }
           },
           "status": {
@@ -758,10 +776,14 @@
           }
         }
       },
-      "readyState": {
+      "readystatechange_event": {
         "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/readyState",
-          "spec_url": "https://xhr.spec.whatwg.org/#states",
+          "description": "<code>readystatechange</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/readystatechange_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-readystatechange",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onreadystatechange"
+          ],
           "support": {
             "chrome": {
               "version_added": "1"
@@ -779,10 +801,10 @@
               "version_added": "4"
             },
             "ie": {
-              "version_added": "7"
+              "version_added": "5"
             },
             "opera": {
-              "version_added": "8"
+              "version_added": "9"
             },
             "opera_android": {
               "version_added": "10.1"
@@ -1831,7 +1853,10 @@
         "__compat": {
           "description": "<code>timeout</code> event",
           "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/timeout_event",
-          "spec_url": "https://xhr.spec.whatwg.org/#event-xhr-timeout",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-timeout",
+            "https://xhr.spec.whatwg.org/#handler-xhr-ontimeout"
+          ],
           "support": {
             "chrome": {
               "version_added": "29"
@@ -1867,7 +1892,7 @@
               "version_added": "1.0"
             },
             "webview_android": {
-              "version_added": "≤37"
+              "version_added": "4.4"
             }
           },
           "status": {
diff --git a/api/XMLHttpRequestEventTarget.json b/api/XMLHttpRequestEventTarget.json
index c0a9789738c7bb..ccb06fc8bec188 100644
--- a/api/XMLHttpRequestEventTarget.json
+++ b/api/XMLHttpRequestEventTarget.json
@@ -47,349 +47,6 @@
           "standard_track": true,
           "deprecated": false
         }
-      },
-      "onabort": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onabort",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onabort",
-          "support": {
-            "chrome": {
-              "version_added": "1"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "3.5"
-            },
-            "firefox_android": {
-              "version_added": "4"
-            },
-            "ie": {
-              "version_added": "10"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "4"
-            },
-            "safari_ios": {
-              "version_added": "3"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "≤37"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "onerror": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onerror",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onerror",
-          "support": {
-            "chrome": {
-              "version_added": "1"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "1"
-            },
-            "firefox_android": {
-              "version_added": "4"
-            },
-            "ie": {
-              "version_added": "10"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "4"
-            },
-            "safari_ios": {
-              "version_added": "3"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "≤37"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "onload": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onload",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onload",
-          "support": {
-            "chrome": {
-              "version_added": "1"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "1"
-            },
-            "firefox_android": {
-              "version_added": "4"
-            },
-            "ie": {
-              "version_added": "9"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "1.3"
-            },
-            "safari_ios": {
-              "version_added": "1"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "≤37"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "onloadend": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onloadend",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onloadend",
-          "support": {
-            "chrome": {
-              "version_added": "18"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "5"
-            },
-            "firefox_android": {
-              "version_added": "5"
-            },
-            "ie": {
-              "version_added": "10"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "6"
-            },
-            "safari_ios": {
-              "version_added": "6"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "4.4"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "onloadstart": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onloadstart",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onloadstart",
-          "support": {
-            "chrome": {
-              "version_added": "1"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "3.5"
-            },
-            "firefox_android": {
-              "version_added": "4"
-            },
-            "ie": {
-              "version_added": "10"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "4"
-            },
-            "safari_ios": {
-              "version_added": "3"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "1"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "onprogress": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/onprogress",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-onprogress",
-          "support": {
-            "chrome": {
-              "version_added": "1"
-            },
-            "chrome_android": {
-              "version_added": "18"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "1"
-            },
-            "firefox_android": {
-              "version_added": "4"
-            },
-            "ie": {
-              "version_added": "10"
-            },
-            "opera": {
-              "version_added": "≤12.1"
-            },
-            "opera_android": {
-              "version_added": "≤12.1"
-            },
-            "safari": {
-              "version_added": "4"
-            },
-            "safari_ios": {
-              "version_added": "3"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "≤37"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
-      },
-      "ontimeout": {
-        "__compat": {
-          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestEventTarget/ontimeout",
-          "spec_url": "https://xhr.spec.whatwg.org/#handler-xhr-ontimeout",
-          "support": {
-            "chrome": {
-              "version_added": "29"
-            },
-            "chrome_android": {
-              "version_added": "29"
-            },
-            "edge": {
-              "version_added": "12"
-            },
-            "firefox": {
-              "version_added": "12"
-            },
-            "firefox_android": {
-              "version_added": "14"
-            },
-            "ie": {
-              "version_added": "8"
-            },
-            "opera": {
-              "version_added": "16"
-            },
-            "opera_android": {
-              "version_added": "16"
-            },
-            "safari": {
-              "version_added": "7"
-            },
-            "safari_ios": {
-              "version_added": "7"
-            },
-            "samsunginternet_android": {
-              "version_added": "1.0"
-            },
-            "webview_android": {
-              "version_added": "4.4"
-            }
-          },
-          "status": {
-            "experimental": false,
-            "standard_track": true,
-            "deprecated": false
-          }
-        }
       }
     }
   }
diff --git a/api/XMLHttpRequestUpload.json b/api/XMLHttpRequestUpload.json
index 9062d16edd4d89..e91576d1304431 100644
--- a/api/XMLHttpRequestUpload.json
+++ b/api/XMLHttpRequestUpload.json
@@ -46,6 +46,377 @@
           "standard_track": true,
           "deprecated": false
         }
+      },
+      "abort_event": {
+        "__compat": {
+          "description": "<code>abort</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/abort_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-abort",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onabort"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "1"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "3.5"
+            },
+            "firefox_android": {
+              "version_added": "4"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "≤37"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "error_event": {
+        "__compat": {
+          "description": "<code>error</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/error_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-error",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onerror"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "1"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "3.5"
+            },
+            "firefox_android": {
+              "version_added": "4"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "≤37"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "load_event": {
+        "__compat": {
+          "description": "<code>load</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/load_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-load",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onload"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "1"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "3.5"
+            },
+            "firefox_android": {
+              "version_added": "4"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "≤37"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "loadend_event": {
+        "__compat": {
+          "description": "<code>loadend</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/loadend_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-loadend",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onloadend"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "18"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "5"
+            },
+            "firefox_android": {
+              "version_added": "5"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "4.4"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "loadstart_event": {
+        "__compat": {
+          "description": "<code>loadstart</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/loadstart_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-loadstart",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onloadstart"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "1"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "3.5"
+            },
+            "firefox_android": {
+              "version_added": "4"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "1"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "progress_event": {
+        "__compat": {
+          "description": "<code>progress</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/progress_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-progress",
+            "https://xhr.spec.whatwg.org/#handler-xhr-onprogress"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "1"
+            },
+            "chrome_android": {
+              "version_added": "18"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "3.5"
+            },
+            "firefox_android": {
+              "version_added": "4"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "≤12.1"
+            },
+            "opera_android": {
+              "version_added": "≤12.1"
+            },
+            "safari": {
+              "version_added": "4"
+            },
+            "safari_ios": {
+              "version_added": "3"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "≤37"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
+      },
+      "timeout_event": {
+        "__compat": {
+          "description": "<code>timeout</code> event",
+          "mdn_url": "https://developer.mozilla.org/docs/Web/API/XMLHttpRequestUpload/timeout_event",
+          "spec_url": [
+            "https://xhr.spec.whatwg.org/#event-xhr-timeout",
+            "https://xhr.spec.whatwg.org/#handler-xhr-ontimeout"
+          ],
+          "support": {
+            "chrome": {
+              "version_added": "29"
+            },
+            "chrome_android": {
+              "version_added": "29"
+            },
+            "edge": {
+              "version_added": "12"
+            },
+            "firefox": {
+              "version_added": "12"
+            },
+            "firefox_android": {
+              "version_added": "14"
+            },
+            "ie": {
+              "version_added": "10"
+            },
+            "opera": {
+              "version_added": "16"
+            },
+            "opera_android": {
+              "version_added": "16"
+            },
+            "safari": {
+              "version_added": "7"
+            },
+            "safari_ios": {
+              "version_added": "7"
+            },
+            "samsunginternet_android": {
+              "version_added": "1.0"
+            },
+            "webview_android": {
+              "version_added": "4.4"
+            }
+          },
+          "status": {
+            "experimental": false,
+            "standard_track": true,
+            "deprecated": false
+          }
+        }
       }
     }
   }