--- a/browser/components/extensions/schemas/context_menus.json
+++ b/browser/components/extensions/schemas/context_menus.json
@@ -98,16 +98,24 @@
             "type": "boolean",
             "optional": true,
             "description": "A flag indicating the state of a checkbox or radio item before it was clicked."
           },
           "checked": {
             "type": "boolean",
             "optional": true,
             "description": "A flag indicating the state of a checkbox or radio item after it is clicked."
+          },
+          "modifiers": {
+            "type": "array",
+            "items": {
+              "type": "string",
+              "enum": ["Shift", "Alt", "Command", "Ctrl", "MacCtrl"]
+            },
+            "description": "An array of keyboard modifiers that were held while the menu item was clicked."
           }
         }
       }
     ],
     "functions": [
       {
         "name": "create",
         "type": "function",