diff --git a/api/Navigator.json b/api/Navigator.json
index f29898e9adf11c..7bedafa9280ed1 100644
--- a/api/Navigator.json
+++ b/api/Navigator.json
@@ -4847,7 +4847,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {
diff --git a/api/WakeLock.json b/api/WakeLock.json
index 862b770447fe1b..d5f317c68b85ea 100644
--- a/api/WakeLock.json
+++ b/api/WakeLock.json
@@ -11,7 +11,7 @@
           "chrome_android": "mirror",
           "edge": "mirror",
           "firefox": {
-            "version_added": false
+            "version_added": "preview"
           },
           "firefox_android": "mirror",
           "ie": {
@@ -44,7 +44,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {
diff --git a/api/WakeLockSentinel.json b/api/WakeLockSentinel.json
index b85dcabac4bacb..8e490e58eea929 100644
--- a/api/WakeLockSentinel.json
+++ b/api/WakeLockSentinel.json
@@ -11,7 +11,7 @@
           "chrome_android": "mirror",
           "edge": "mirror",
           "firefox": {
-            "version_added": false
+            "version_added": "preview"
           },
           "firefox_android": "mirror",
           "ie": {
@@ -44,7 +44,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {
@@ -79,7 +79,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {
@@ -113,7 +113,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {
@@ -147,7 +147,7 @@
             "chrome_android": "mirror",
             "edge": "mirror",
             "firefox": {
-              "version_added": false
+              "version_added": "preview"
             },
             "firefox_android": "mirror",
             "ie": {