diff --git a/experimenter/experimenter/features/manifests/fenix/.ref-cache.yaml b/experimenter/experimenter/features/manifests/fenix/.ref-cache.yaml
index ad7b341127..ad110b9865 100644
--- a/experimenter/experimenter/features/manifests/fenix/.ref-cache.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/.ref-cache.yaml
@@ -1,3 +1,3 @@
-beta: 93fdd4234be5673a174351922a8be796cefcad65
-master: 26ad7aaffe02c4f9ab84c0faf5bc2f4dc4583806
+beta: a64cc659cd6532fb4e838d76c71f6162076cba17
+master: e24277e20c492b4a785b4488af02cca062ec7c2c
 release: d8f30fc43d8a411937b53bb95eb9555356e9bcb8
diff --git a/experimenter/experimenter/features/manifests/fenix/beta.fml.yaml b/experimenter/experimenter/features/manifests/fenix/beta.fml.yaml
index acf2ad4341..d68d0e1e44 100644
--- a/experimenter/experimenter/features/manifests/fenix/beta.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/beta.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/developer.fml.yaml b/experimenter/experimenter/features/manifests/fenix/developer.fml.yaml
index c3606ed74c..517bc02740 100644
--- a/experimenter/experimenter/features/manifests/fenix/developer.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/developer.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/experimenter.yaml b/experimenter/experimenter/features/manifests/fenix/experimenter.yaml
index 1dc5541d02..7409d0b772 100644
--- a/experimenter/experimenter/features/manifests/fenix/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/experimenter.yaml
@@ -34,6 +34,17 @@ cookie-banners:
     sections-enabled:
       type: json
       description: This property provides a lookup table of whether or not the given section should be enabled.
+encourage-search-cfr:
+  description: A feature that shows a CFR on first launch to encourage users to make a search
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    cfrText:
+      type: string
+      description: The text to show in the CFR
+    enabled:
+      type: boolean
+      description: "When true, the CFR will show"
 fingerprinting-protection:
   description: Control Fingerprinting Protection
   hasExposure: true
diff --git a/experimenter/experimenter/features/manifests/fenix/nightly.fml.yaml b/experimenter/experimenter/features/manifests/fenix/nightly.fml.yaml
index 198ff574e5..edcbcfeedf 100644
--- a/experimenter/experimenter/features/manifests/fenix/nightly.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/nightly.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/release.fml.yaml b/experimenter/experimenter/features/manifests/fenix/release.fml.yaml
index 01739864d1..5743e0dc57 100644
--- a/experimenter/experimenter/features/manifests/fenix/release.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/release.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/v136.0.0/beta.fml.yaml b/experimenter/experimenter/features/manifests/fenix/v136.0.0/beta.fml.yaml
index acf2ad4341..d68d0e1e44 100644
--- a/experimenter/experimenter/features/manifests/fenix/v136.0.0/beta.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/v136.0.0/beta.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/v136.0.0/developer.fml.yaml b/experimenter/experimenter/features/manifests/fenix/v136.0.0/developer.fml.yaml
index c3606ed74c..517bc02740 100644
--- a/experimenter/experimenter/features/manifests/fenix/v136.0.0/developer.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/v136.0.0/developer.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/v136.0.0/experimenter.yaml b/experimenter/experimenter/features/manifests/fenix/v136.0.0/experimenter.yaml
index 1dc5541d02..7409d0b772 100644
--- a/experimenter/experimenter/features/manifests/fenix/v136.0.0/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/v136.0.0/experimenter.yaml
@@ -34,6 +34,17 @@ cookie-banners:
     sections-enabled:
       type: json
       description: This property provides a lookup table of whether or not the given section should be enabled.
+encourage-search-cfr:
+  description: A feature that shows a CFR on first launch to encourage users to make a search
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    cfrText:
+      type: string
+      description: The text to show in the CFR
+    enabled:
+      type: boolean
+      description: "When true, the CFR will show"
 fingerprinting-protection:
   description: Control Fingerprinting Protection
   hasExposure: true
diff --git a/experimenter/experimenter/features/manifests/fenix/v136.0.0/nightly.fml.yaml b/experimenter/experimenter/features/manifests/fenix/v136.0.0/nightly.fml.yaml
index 198ff574e5..edcbcfeedf 100644
--- a/experimenter/experimenter/features/manifests/fenix/v136.0.0/nightly.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/v136.0.0/nightly.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/fenix/v136.0.0/release.fml.yaml b/experimenter/experimenter/features/manifests/fenix/v136.0.0/release.fml.yaml
index 01739864d1..5743e0dc57 100644
--- a/experimenter/experimenter/features/manifests/fenix/v136.0.0/release.fml.yaml
+++ b/experimenter/experimenter/features/manifests/fenix/v136.0.0/release.fml.yaml
@@ -46,6 +46,17 @@ features:
           feature-setting-detect-only: 0
           feature-setting-global-rules: 1
           feature-setting-global-rules-sub-frames: 1
+  encourage-search-cfr:
+    description: A feature that shows a CFR on first launch to encourage users to make a search
+    variables:
+      cfrText:
+        description: The text to show in the CFR
+        type: Text
+        default: ""
+      enabled:
+        description: "When true, the CFR will show"
+        type: Boolean
+        default: false
   fingerprinting-protection:
     description: Control Fingerprinting Protection
     variables:
diff --git a/experimenter/experimenter/features/manifests/firefox-desktop/.ref-cache.yaml b/experimenter/experimenter/features/manifests/firefox-desktop/.ref-cache.yaml
index 864251d40a..3670efc68f 100644
--- a/experimenter/experimenter/features/manifests/firefox-desktop/.ref-cache.yaml
+++ b/experimenter/experimenter/features/manifests/firefox-desktop/.ref-cache.yaml
@@ -1,5 +1,5 @@
-beta: a1e5d1f58aca7129af9148ced4bd6e8781b3aeb4
-central: dd9f5a143dd227e6a6271b78458950bfd6736161
+beta: 2f218da698db4f92722be65f51a6e53d24321cec
+central: a568ac65fd4e6833bbee5cc341b3031de12f41a6
 esr115: dc8b700b41911c2bde2cff62bde16d3c0ceadc2a
 esr128: a7c935b8a7c0c39bd2161d0927e9f2f2eb4c9d47
 release: 8c35adfaf5ea8b07c3e221d0c9d557a1375f5852
diff --git a/experimenter/experimenter/features/manifests/firefox-desktop/experimenter.yaml b/experimenter/experimenter/features/manifests/firefox-desktop/experimenter.yaml
index b1199d4b58..fea84dd44a 100644
--- a/experimenter/experimenter/features/manifests/firefox-desktop/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/firefox-desktop/experimenter.yaml
@@ -4040,12 +4040,23 @@ bounceTrackingProtection:
   owner: emz@mozilla.com
   hasExposure: false
   variables:
-    enabled:
+    mode:
       type: int
       setPref:
         branch: default
         pref: privacy.bounceTrackingProtection.mode
-      description: Mode to run the feature in. See nsIBounceTrackingProtection.idl for documentation.
+      description: >-
+        Mode to run the feature in. See nsIBounceTrackingProtection.idl for
+        documentation.
+    requireStatefulBounces:
+      type: boolean
+      setPref:
+        branch: default
+        pref: privacy.bounceTrackingProtection.requireStatefulBounces
+      description: >-
+        If true, only bounce redirects where the middle hop/s access cookies or
+        storage will be considered to be bounce trackers. If false, all
+        redirects that fit the bounce tracker heuristic will be considered.
 
 remoteTabManagement:
   description: >
diff --git a/experimenter/experimenter/features/manifests/firefox-desktop/v136.0.0/experimenter.yaml b/experimenter/experimenter/features/manifests/firefox-desktop/v136.0.0/experimenter.yaml
index b1199d4b58..fea84dd44a 100644
--- a/experimenter/experimenter/features/manifests/firefox-desktop/v136.0.0/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/firefox-desktop/v136.0.0/experimenter.yaml
@@ -4040,12 +4040,23 @@ bounceTrackingProtection:
   owner: emz@mozilla.com
   hasExposure: false
   variables:
-    enabled:
+    mode:
       type: int
       setPref:
         branch: default
         pref: privacy.bounceTrackingProtection.mode
-      description: Mode to run the feature in. See nsIBounceTrackingProtection.idl for documentation.
+      description: >-
+        Mode to run the feature in. See nsIBounceTrackingProtection.idl for
+        documentation.
+    requireStatefulBounces:
+      type: boolean
+      setPref:
+        branch: default
+        pref: privacy.bounceTrackingProtection.requireStatefulBounces
+      description: >-
+        If true, only bounce redirects where the middle hop/s access cookies or
+        storage will be considered to be bounce trackers. If false, all
+        redirects that fit the bounce tracker heuristic will be considered.
 
 remoteTabManagement:
   description: >
diff --git a/experimenter/experimenter/features/manifests/focus-ios/.ref-cache.yaml b/experimenter/experimenter/features/manifests/focus-ios/.ref-cache.yaml
index 9ff7c758b2..0c2cbd61cf 100644
--- a/experimenter/experimenter/features/manifests/focus-ios/.ref-cache.yaml
+++ b/experimenter/experimenter/features/manifests/focus-ios/.ref-cache.yaml
@@ -13,7 +13,7 @@ focus/klar-v131.1: b7dca2271b14988837524a30eb154d91eb5e4912
 focus/klar-v132.0: d9ed6134db59ff456d343e2bb211aefd040319ac
 focus/klar-v133.0: a3372669a06fa684d3c5945c317d6787e3125303
 focus/klar-v134.0: be550d94c2c7bc8b8902cdf7fe542a64e73a381a
-main: 62258e345b377b98e67de79cd1cec6d3f918a3e2
+main: 16d6776700510def815da6b13fcd4099571ef31d
 release/v124: da250bed9e19c4978d4400d6d404cb312e33636e
 release/v125: a3e1e0773a00009e08d95726fd518ab642255ccd
 release/v126: 6f305409b4af68e8404401a2caad8cb0da9a0494
@@ -25,4 +25,4 @@ release/v131: 7444df581b62d357df12ddc3c90d821d940efbb8
 release/v132: cb318d0061ec6354167ecc1968020d5d75f1bffc
 release/v133: 7c651ce29e94c6389af7a69ec6b5c44251976e92
 release/v134: 846f290dfd0627f1873a524da439ebd7a1a4a932
-release/v135: a407f3705c6a6134ac84ff3d9e99d6fa4d5fd0fb
+release/v135: 97d52f4eb357afc7cc73dfdf94ab6a585da2cf12
diff --git a/experimenter/experimenter/features/manifests/ios/.ref-cache.yaml b/experimenter/experimenter/features/manifests/ios/.ref-cache.yaml
index a76cbeecfa..6bcdeb2141 100644
--- a/experimenter/experimenter/features/manifests/ios/.ref-cache.yaml
+++ b/experimenter/experimenter/features/manifests/ios/.ref-cache.yaml
@@ -1,4 +1,4 @@
-main: 62258e345b377b98e67de79cd1cec6d3f918a3e2
+main: 16d6776700510def815da6b13fcd4099571ef31d
 release/v117: 43b690c450066d4dde1b2ccb93ed3714d244d502
 release/v118: 89a7ea3c3372e5a4ef5b3c5b85499d26198d0524
 release/v119: 7dc381f991c6d2a983c3ba7f0cffd880e8c29e7b
@@ -17,7 +17,7 @@ release/v131: 7444df581b62d357df12ddc3c90d821d940efbb8
 release/v132: cb318d0061ec6354167ecc1968020d5d75f1bffc
 release/v133: 7c651ce29e94c6389af7a69ec6b5c44251976e92
 release/v134: 846f290dfd0627f1873a524da439ebd7a1a4a932
-release/v135: a407f3705c6a6134ac84ff3d9e99d6fa4d5fd0fb
+release/v135: 97d52f4eb357afc7cc73dfdf94ab6a585da2cf12
 v117.0: 3b275ab1e4ccef769d84437033c0c68acfd2df8a
 v117.1: 55ddcf473a65d106d43f6d2ae5af4076d6d03688
 v117.2: 5cc367aa8857199cd8a54d53e8faf6696c5614c3
diff --git a/experimenter/experimenter/features/manifests/ios/beta.fml.yaml b/experimenter/experimenter/features/manifests/ios/beta.fml.yaml
index 1900fa7de5..93da728494 100644
--- a/experimenter/experimenter/features/manifests/ios/beta.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/beta.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/developer.fml.yaml b/experimenter/experimenter/features/manifests/ios/developer.fml.yaml
index ce44305c20..4617778a73 100644
--- a/experimenter/experimenter/features/manifests/ios/developer.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/developer.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/experimenter.yaml b/experimenter/experimenter/features/manifests/ios/experimenter.yaml
index e1a08aa9ac..2ac1c6c678 100644
--- a/experimenter/experimenter/features/manifests/ios/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/ios/experimenter.yaml
@@ -96,6 +96,14 @@ homescreenFeature:
     sections-enabled:
       type: json
       description: "This property provides a lookup table of whether or not the given section should be enabled. If the section is enabled, it should be toggleable in the settings screen, and on by default.\n"
+js-alert-refactor:
+  description: "This feature is for the JavaScript Webview refactor\n"
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    enabled:
+      type: boolean
+      description: "When true this enables the new JS alerts system to be used\n"
 login-autofill:
   description: This property defines the login autofill feature for automatically filling in usernames and passwords.
   hasExposure: true
diff --git a/experimenter/experimenter/features/manifests/ios/release.fml.yaml b/experimenter/experimenter/features/manifests/ios/release.fml.yaml
index e02df600a2..3a316cedeb 100644
--- a/experimenter/experimenter/features/manifests/ios/release.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/release.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: false
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v135.0.0/beta.fml.yaml b/experimenter/experimenter/features/manifests/ios/v135.0.0/beta.fml.yaml
index 1900fa7de5..93da728494 100644
--- a/experimenter/experimenter/features/manifests/ios/v135.0.0/beta.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v135.0.0/beta.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v135.0.0/developer.fml.yaml b/experimenter/experimenter/features/manifests/ios/v135.0.0/developer.fml.yaml
index ce44305c20..4617778a73 100644
--- a/experimenter/experimenter/features/manifests/ios/v135.0.0/developer.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v135.0.0/developer.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v135.0.0/experimenter.yaml b/experimenter/experimenter/features/manifests/ios/v135.0.0/experimenter.yaml
index e1a08aa9ac..2ac1c6c678 100644
--- a/experimenter/experimenter/features/manifests/ios/v135.0.0/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v135.0.0/experimenter.yaml
@@ -96,6 +96,14 @@ homescreenFeature:
     sections-enabled:
       type: json
       description: "This property provides a lookup table of whether or not the given section should be enabled. If the section is enabled, it should be toggleable in the settings screen, and on by default.\n"
+js-alert-refactor:
+  description: "This feature is for the JavaScript Webview refactor\n"
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    enabled:
+      type: boolean
+      description: "When true this enables the new JS alerts system to be used\n"
 login-autofill:
   description: This property defines the login autofill feature for automatically filling in usernames and passwords.
   hasExposure: true
diff --git a/experimenter/experimenter/features/manifests/ios/v135.0.0/release.fml.yaml b/experimenter/experimenter/features/manifests/ios/v135.0.0/release.fml.yaml
index e02df600a2..3a316cedeb 100644
--- a/experimenter/experimenter/features/manifests/ios/v135.0.0/release.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v135.0.0/release.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: false
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v136.0.0/beta.fml.yaml b/experimenter/experimenter/features/manifests/ios/v136.0.0/beta.fml.yaml
index 1900fa7de5..93da728494 100644
--- a/experimenter/experimenter/features/manifests/ios/v136.0.0/beta.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v136.0.0/beta.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v136.0.0/developer.fml.yaml b/experimenter/experimenter/features/manifests/ios/v136.0.0/developer.fml.yaml
index ce44305c20..4617778a73 100644
--- a/experimenter/experimenter/features/manifests/ios/v136.0.0/developer.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v136.0.0/developer.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: true
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables:
diff --git a/experimenter/experimenter/features/manifests/ios/v136.0.0/experimenter.yaml b/experimenter/experimenter/features/manifests/ios/v136.0.0/experimenter.yaml
index e1a08aa9ac..2ac1c6c678 100644
--- a/experimenter/experimenter/features/manifests/ios/v136.0.0/experimenter.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v136.0.0/experimenter.yaml
@@ -96,6 +96,14 @@ homescreenFeature:
     sections-enabled:
       type: json
       description: "This property provides a lookup table of whether or not the given section should be enabled. If the section is enabled, it should be toggleable in the settings screen, and on by default.\n"
+js-alert-refactor:
+  description: "This feature is for the JavaScript Webview refactor\n"
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    enabled:
+      type: boolean
+      description: "When true this enables the new JS alerts system to be used\n"
 login-autofill:
   description: This property defines the login autofill feature for automatically filling in usernames and passwords.
   hasExposure: true
diff --git a/experimenter/experimenter/features/manifests/ios/v136.0.0/release.fml.yaml b/experimenter/experimenter/features/manifests/ios/v136.0.0/release.fml.yaml
index e02df600a2..3a316cedeb 100644
--- a/experimenter/experimenter/features/manifests/ios/v136.0.0/release.fml.yaml
+++ b/experimenter/experimenter/features/manifests/ios/v136.0.0/release.fml.yaml
@@ -101,6 +101,13 @@ features:
         default:
           jump-back-in: true
           recent-explorations: false
+  js-alert-refactor:
+    description: "This feature is for the JavaScript Webview refactor\n"
+    variables:
+      enabled:
+        description: "When true this enables the new JS alerts system to be used\n"
+        type: Boolean
+        default: false
   login-autofill:
     description: This property defines the login autofill feature for automatically filling in usernames and passwords.
     variables: