diff --git a/css/properties/content.json b/css/properties/content.json
index fb133813a324f8..9a974810e5bfb2 100644
--- a/css/properties/content.json
+++ b/css/properties/content.json
@@ -76,6 +76,47 @@
               "standard_track": true,
               "deprecated": false
             }
+          },
+          "counters": {
+            "__compat": {
+              "description": "`counter()` and `counters()` in alternative text",
+              "tags": [
+                "web-features:alt-text-generated-content"
+              ],
+              "support": {
+                "chrome": [
+                  {
+                    "version_added": "preview"
+                  },
+                  {
+                    "version_added": "140",
+                    "partial_implementation": true,
+                    "notes": "Counters are recognised, but the spoken values do not increment"
+                  }
+                ],
+                "chrome_android": "mirror",
+                "edge": "mirror",
+                "firefox": {
+                  "version_added": false
+                },
+                "firefox_android": "mirror",
+                "oculus": "mirror",
+                "opera": "mirror",
+                "opera_android": "mirror",
+                "safari": {
+                  "version_added": false
+                },
+                "safari_ios": "mirror",
+                "samsunginternet_android": "mirror",
+                "webview_android": "mirror",
+                "webview_ios": "mirror"
+              },
+              "status": {
+                "experimental": true,
+                "standard_track": true,
+                "deprecated": false
+              }
+            }
           }
         },
         "close-quote": {