diff --git a/webextensions/api/proxy.json b/webextensions/api/proxy.json
index bbd3fad9ca259d..975817132f590f 100644
--- a/webextensions/api/proxy.json
+++ b/webextensions/api/proxy.json
@@ -30,7 +30,8 @@
               },
               "edge": "mirror",
               "firefox": {
-                "version_added": "60"
+                "version_added": "60",
+                "notes": "Support for MASQUE proxies added in Firefox 145."
               },
               "firefox_android": "mirror",
               "opera": "mirror",
@@ -40,6 +41,26 @@
               "safari_ios": "mirror"
             }
           },
+          "masqueTemplate": {
+            "__compat": {
+              "support": {
+                "chrome": {
+                  "version_added": false
+                },
+                "edge": "mirror",
+                "firefox": {
+                  "version_added": "146",
+                  "notes": "Was available as `pathTemplate` in Firefox 145."
+                },
+                "firefox_android": "mirror",
+                "opera": "mirror",
+                "safari": {
+                  "version_added": false
+                },
+                "safari_ios": "mirror"
+              }
+            }
+          },
           "proxyAuthorizationHeader": {
             "__compat": {
               "support": {