diff --git a/mathml/elements/mmultiscripts.json b/mathml/elements/mmultiscripts.json
index f2ede5215595c..be46202f790a7 100644
--- a/mathml/elements/mmultiscripts.json
+++ b/mathml/elements/mmultiscripts.json
@@ -32,9 +32,7 @@
             "safari": {
               "version_added": "6"
             },
-            "safari_ios": {
-              "version_added": false
-            },
+            "safari_ios": "mirror",
             "samsunginternet_android": "mirror",
             "webview_android": "mirror"
           },
@@ -43,6 +41,72 @@
             "standard_track": true,
             "deprecated": false
           }
+        },
+        "subscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
+        },
+        "superscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
         }
       }
     }
diff --git a/mathml/elements/msub.json b/mathml/elements/msub.json
index 99817ba79af5b..98484cb11ef61 100644
--- a/mathml/elements/msub.json
+++ b/mathml/elements/msub.json
@@ -32,9 +32,7 @@
             "safari": {
               "version_added": "6"
             },
-            "safari_ios": {
-              "version_added": false
-            },
+            "safari_ios": "mirror",
             "samsunginternet_android": "mirror",
             "webview_android": "mirror"
           },
@@ -43,6 +41,39 @@
             "standard_track": true,
             "deprecated": false
           }
+        },
+        "subscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
         }
       }
     }
diff --git a/mathml/elements/msubsup.json b/mathml/elements/msubsup.json
index 3778969980884..8f87bb97eb3b5 100644
--- a/mathml/elements/msubsup.json
+++ b/mathml/elements/msubsup.json
@@ -32,9 +32,7 @@
             "safari": {
               "version_added": "6"
             },
-            "safari_ios": {
-              "version_added": false
-            },
+            "safari_ios": "mirror",
             "samsunginternet_android": "mirror",
             "webview_android": "mirror"
           },
@@ -43,6 +41,72 @@
             "standard_track": true,
             "deprecated": false
           }
+        },
+        "subscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
+        },
+        "superscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
         }
       }
     }
diff --git a/mathml/elements/msup.json b/mathml/elements/msup.json
index 0b8b30d8ab217..8146bcdd951b2 100644
--- a/mathml/elements/msup.json
+++ b/mathml/elements/msup.json
@@ -32,9 +32,7 @@
             "safari": {
               "version_added": "6"
             },
-            "safari_ios": {
-              "version_added": false
-            },
+            "safari_ios": "mirror",
             "samsunginternet_android": "mirror",
             "webview_android": "mirror"
           },
@@ -43,6 +41,39 @@
             "standard_track": true,
             "deprecated": false
           }
+        },
+        "superscriptshift": {
+          "__compat": {
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": "1",
+                "version_removed": "83"
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "7"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": true
+            }
+          }
         }
       }
     }