diff --git a/CLOBBER b/CLOBBER
index b012582fbc5e..ffc68934d7a8 100644
--- a/CLOBBER
+++ b/CLOBBER
@@ -22,4 +22,4 @@
 # changes to stick? As of bug 928195, this shouldn't be necessary! Please
 # don't change CLOBBER for WebIDL changes any more.
 
-Modified build files in third_party/libwebrtc - Bug 1952339 - Vendor libwebrtc from a416f1c7a9
+Merge day clobber 2025-04-28
\ No newline at end of file
diff --git a/browser/config/version.txt b/browser/config/version.txt
index c74df6724a13..37f18177186e 100644
--- a/browser/config/version.txt
+++ b/browser/config/version.txt
@@ -1 +1 @@
-139.0a1
+140.0a1
diff --git a/browser/config/version_display.txt b/browser/config/version_display.txt
index c74df6724a13..37f18177186e 100644
--- a/browser/config/version_display.txt
+++ b/browser/config/version_display.txt
@@ -1 +1 @@
-139.0a1
+140.0a1
diff --git a/browser/extensions/newtab/manifest.json b/browser/extensions/newtab/manifest.json
index 689e7f8b22bb..0bfd74cf5360 100644
--- a/browser/extensions/newtab/manifest.json
+++ b/browser/extensions/newtab/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version": 2,
   "name": "New Tab",
   "description": "",
-  "version": "139.0.0",
+  "version": "140.0.0",
 
   "browser_specific_settings": {
     "gecko": {
diff --git a/browser/extensions/webcompat/manifest.json b/browser/extensions/webcompat/manifest.json
index 23ca04feed95..17dcb551e5e7 100644
--- a/browser/extensions/webcompat/manifest.json
+++ b/browser/extensions/webcompat/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version": 2,
   "name": "Web Compatibility Interventions",
   "description": "Urgent post-release fixes for web compatibility.",
-  "version": "139.12.0",
+  "version": "140.0.0",
   "browser_specific_settings": {
     "gecko": {
       "id": "webcompat@mozilla.org",
diff --git a/config/milestone.txt b/config/milestone.txt
index f5f1fad95a37..396c13a0f0f8 100644
--- a/config/milestone.txt
+++ b/config/milestone.txt
@@ -10,4 +10,4 @@
 # hardcoded milestones in the tree from these two files.
 #--------------------------------------------------------
 
-139.0a1
+140.0a1
diff --git a/mobile/android/version.txt b/mobile/android/version.txt
index c74df6724a13..37f18177186e 100644
--- a/mobile/android/version.txt
+++ b/mobile/android/version.txt
@@ -1 +1 @@
-139.0a1
+140.0a1
diff --git a/services/sync/modules/constants.sys.mjs b/services/sync/modules/constants.sys.mjs
index cb92dded88aa..fd17ead99349 100644
--- a/services/sync/modules/constants.sys.mjs
+++ b/services/sync/modules/constants.sys.mjs
@@ -4,7 +4,7 @@
 
 // Don't manually modify this line, as it is automatically replaced on merge day
 // by the gecko_migration.py script.
-export const WEAVE_VERSION = "1.141.0";
+export const WEAVE_VERSION = "1.142.0";
 
 // Sync Server API version that the client supports.
 export const SYNC_API_VERSION = "1.5";