diff --git a/src/firefox-patches/148_macos_sdk_26_2.patch b/src/firefox-patches/148_macos_sdk_26_2.patch
new file mode 100644
index 000000000..9853566f2
--- /dev/null
+++ b/src/firefox-patches/148_macos_sdk_26_2.patch
@@ -0,0 +1,248 @@
+diff --git a/build/moz.configure/toolchain.configure b/build/moz.configure/toolchain.configure
+--- a/build/moz.configure/toolchain.configure
++++ b/build/moz.configure/toolchain.configure
+@@ -231,11 +231,11 @@
+         nargs=1,
+         help="Location of platform SDK to use",
+     )
+ 
+     def mac_sdk_min_version():
+-        return "26.1"
++        return "26.2"
+ 
+     @depends(
+         "--with-macos-sdk",
+         host,
+         bootstrap_path(
+diff --git a/taskcluster/kinds/toolchain/macos-sdk.yml b/taskcluster/kinds/toolchain/macos-sdk.yml
+--- a/taskcluster/kinds/toolchain/macos-sdk.yml
++++ b/taskcluster/kinds/toolchain/macos-sdk.yml
+@@ -28,24 +28,24 @@
+             - https://swcdn.apple.com/content/downloads/15/62/032-84673-A_7A1TG1RF8Z/xpc8q44ggn2pkn82iwr0fi1zeb9cxi8ath/CLTools_macOSNMOS_SDK.pkg
+             - 8de3306508dca31040b3b49ff370e96c94f4546bcf22cb4069abbb18e2d6bce8e20d40a6903f00ae75558175b624a979ea0444f54bc6d9d67e841f2000b0d863
+             - Library/Developer/CommandLineTools/SDKs/MacOSX13.3.sdk
+         toolchain-artifact: project/gecko/mac-sdk/MacOSX13.3.sdk.tar.zst
+ 
+-macosx64-sdk-26.1:
+-    description: "macOS 26.1 SDK"
++macosx64-sdk-26.2:
++    description: "macOS 26.2 SDK"
+     treeherder:
+-        symbol: TM(sdk26.1)
++        symbol: TM(sdk26.2)
+     run:
+         arguments:
+-            - https://swcdn.apple.com/content/downloads/22/09/093-00219-A_WIA1LP39TY/evbam2mb02xqr05ju9ddb95y8qil8kz9tm/CLTools_macOSNMOS_SDK.pkg
+-            - f6a5f44b3652f5abdf7ad2602f54ad38774404f45264a4e70cfccc58b8b39aed2a89f74ef22c44bf932d0a55b062ebc3651f73fa06ff755ee5da53b9dcc62fba
+-            - Library/Developer/CommandLineTools/SDKs/MacOSX26.1.sdk
+-        toolchain-artifact: project/gecko/mac-sdk/MacOSX26.1.sdk.tar.zst
++            - https://swcdn.apple.com/content/downloads/60/22/089-71960-A_W8BL1RUJJ6/5zkyplomhk1cm7z6xja2ktgapnhhti6wwd/CLTools_macOSNMOS_SDK.pkg
++            - f3785f1bbc3b8323121b66fc28ef59083b4f508c7bdabb9d8d916f142ee89b01cb8030eba469eb9107b416d1c9d523a1d2e009cddb83536a819a3704a5d3ce17
++            - Library/Developer/CommandLineTools/SDKs/MacOSX26.2.sdk
++        toolchain-artifact: project/gecko/mac-sdk/MacOSX26.2.sdk.tar.zst
+         toolchain-alias:
+             - macosx64-sdk
+             - macosx64-sdk-toolchain
+-            - MacOSX26.1.sdk
++            - MacOSX26.2.sdk
+ 
+ ios-sdk-18.4:
+     description: "iPhoneOS18.4 SDK"
+     treeherder:
+         symbol: TM(ios18.4)
+diff --git a/taskcluster/scripts/misc/build-cpython.sh b/taskcluster/scripts/misc/build-cpython.sh
+--- a/taskcluster/scripts/misc/build-cpython.sh
++++ b/taskcluster/scripts/misc/build-cpython.sh
+@@ -35,11 +35,11 @@
+                 macosx_version_min=10.15
+                 ;;
+         esac
+         # NOTE: both CFLAGS and CPPFLAGS need to be set here, otherwise
+         # configure step fails.
+-        sysroot_flags="-isysroot ${MOZ_FETCHES_DIR}/MacOSX26.1.sdk -mmacosx-version-min=${macosx_version_min}"
++        sysroot_flags="-isysroot ${MOZ_FETCHES_DIR}/MacOSX26.2.sdk -mmacosx-version-min=${macosx_version_min}"
+         export CPPFLAGS="${sysroot_flags} -I${xz_prefix}/include"
+         export CFLAGS=${sysroot_flags}
+         export LDFLAGS="${LDFLAGS} ${sysroot_flags} -L${xz_prefix}/lib"
+         configure_flags_extra=--with-openssl=/usr/local/opt/openssl
+ 
+diff --git a/taskcluster/scripts/misc/build-custom-car.sh b/taskcluster/scripts/misc/build-custom-car.sh
+--- a/taskcluster/scripts/misc/build-custom-car.sh
++++ b/taskcluster/scripts/misc/build-custom-car.sh
+@@ -58,11 +58,11 @@
+ fi
+ 
+ # Logic for macosx64
+ if [[ $(uname -s) == "Darwin" ]]; then
+   # Modify the config with fetched sdk path
+-  export MACOS_SYSROOT="$MOZ_FETCHES_DIR/MacOSX26.1.sdk"
++  export MACOS_SYSROOT="$MOZ_FETCHES_DIR/MacOSX26.2.sdk"
+   # Bug 1990712 & 1989676
+   # HACK: Create a stub DarwinBasic.modulemap to satisfy Ninja’s dependency graph.
+   # This file does not exist in Command Line Tools SDKs. It seems only the full
+   # Xcode SDK includes DarwinBasic/DarwinFoundation modulemaps.
+   mkdir -p "$MACOS_SYSROOT/usr/include"
+diff --git a/taskcluster/scripts/misc/build-geckodriver.sh b/taskcluster/scripts/misc/build-geckodriver.sh
+--- a/taskcluster/scripts/misc/build-geckodriver.sh
++++ b/taskcluster/scripts/misc/build-geckodriver.sh
+@@ -23,11 +23,11 @@
+   export TARGET_CXXFLAGS="-Xclang -ivfsoverlay -Xclang $MOZ_FETCHES_DIR/vs/overlay.yaml"
+   ;;
+ # OSX cross builds are a bit harder
+ *-apple-darwin)
+   export PATH="$MOZ_FETCHES_DIR/clang/bin:$PATH"
+-  RUSTFLAGS="-Clinker=$MOZ_FETCHES_DIR/clang/bin/clang++ -C link-arg=-isysroot -C link-arg=$MOZ_FETCHES_DIR/MacOSX26.1.sdk -C link-arg=-fuse-ld=lld -C link-arg=--target=$TARGET"
++  RUSTFLAGS="-Clinker=$MOZ_FETCHES_DIR/clang/bin/clang++ -C link-arg=-isysroot -C link-arg=$MOZ_FETCHES_DIR/MacOSX26.2.sdk -C link-arg=-fuse-ld=lld -C link-arg=--target=$TARGET"
+   if test "$TARGET" = "aarch64-apple-darwin"; then
+       export MACOSX_DEPLOYMENT_TARGET=11.0
+   else
+       export MACOSX_DEPLOYMENT_TARGET=10.15
+   fi
+diff --git a/taskcluster/scripts/misc/build-gn-macosx.sh b/taskcluster/scripts/misc/build-gn-macosx.sh
+--- a/taskcluster/scripts/misc/build-gn-macosx.sh
++++ b/taskcluster/scripts/misc/build-gn-macosx.sh
+@@ -3,11 +3,11 @@
+ 
+ # This script is for building GN.
+ 
+ WORKSPACE=$HOME/workspace
+ 
+-CROSS_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.1.sdk
++CROSS_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.2.sdk
+ export MACOSX_DEPLOYMENT_TARGET=10.15
+ 
+ export CC=$MOZ_FETCHES_DIR/clang/bin/clang
+ export CXX=$MOZ_FETCHES_DIR/clang/bin/clang++
+ export AR=$MOZ_FETCHES_DIR/clang/bin/llvm-ar
+diff --git a/taskcluster/scripts/misc/build-llvm-common.sh b/taskcluster/scripts/misc/build-llvm-common.sh
+--- a/taskcluster/scripts/misc/build-llvm-common.sh
++++ b/taskcluster/scripts/misc/build-llvm-common.sh
+@@ -37,15 +37,15 @@
+     $EXTRA_CMAKE_FLAGS
+     -DCMAKE_LINKER=$MOZ_FETCHES_DIR/clang/bin/ld64.lld
+     -DCMAKE_LIPO=$MOZ_FETCHES_DIR/clang/bin/llvm-lipo
+     -DCMAKE_SYSTEM_NAME=Darwin
+     -DCMAKE_SYSTEM_VERSION=$MACOSX_DEPLOYMENT_TARGET
+-    -DCMAKE_OSX_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.1.sdk
++    -DCMAKE_OSX_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.2.sdk
+     -DCMAKE_EXE_LINKER_FLAGS=-fuse-ld=lld
+     -DCMAKE_SHARED_LINKER_FLAGS=-fuse-ld=lld
+     -DDARWIN_osx_ARCHS=$arch
+-    -DDARWIN_osx_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.1.sdk
++    -DDARWIN_osx_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.2.sdk
+     -DDARWIN_macosx_OVERRIDE_SDK_VERSION=11.0
+     -DDARWIN_osx_BUILTIN_ARCHS=$arch
+     -DLLVM_DEFAULT_TARGET_TRIPLE=$target
+   "
+   # compiler-rt build script expects to find `codesign` in $PATH.
+diff --git a/taskcluster/scripts/misc/build-nasm.sh b/taskcluster/scripts/misc/build-nasm.sh
+--- a/taskcluster/scripts/misc/build-nasm.sh
++++ b/taskcluster/scripts/misc/build-nasm.sh
+@@ -36,17 +36,17 @@
+         EXE=.exe
+         ;;
+     macosx64)
+         export MACOSX_DEPLOYMENT_TARGET=10.15
+         TARGET=x86_64-apple-darwin
+-        CC="clang -fuse-ld=lld --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.1.sdk"
++        CC="clang -fuse-ld=lld --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.2.sdk"
+         EXE=
+ 	;;
+     macosx64-aarch64)
+         export MACOSX_DEPLOYMENT_TARGET=11.0
+         TARGET=aarch64-apple-darwin
+-        CC="clang -fuse-ld=lld --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.1.sdk"
++        CC="clang -fuse-ld=lld --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.2.sdk"
+         EXE=
+ 	;;
+     *)
+         CC="clang --sysroot=$MOZ_FETCHES_DIR/sysroot-x86_64-linux-gnu"
+         EXE=
+diff --git a/taskcluster/scripts/misc/build-pkgconf.sh b/taskcluster/scripts/misc/build-pkgconf.sh
+--- a/taskcluster/scripts/misc/build-pkgconf.sh
++++ b/taskcluster/scripts/misc/build-pkgconf.sh
+@@ -19,17 +19,17 @@
+     EXE=
+     ;;
+ x86_64-apple-darwin)
+     export MACOSX_DEPLOYMENT_TARGET=10.15
+     TARGET=$1
+-    CC="clang --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.1.sdk"
++    CC="clang --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.2.sdk"
+     EXE=
+     ;;
+ aarch64-apple-darwin)
+     export MACOSX_DEPLOYMENT_TARGET=11.0
+     TARGET=$1
+-    CC="clang --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.1.sdk"
++    CC="clang --target=$TARGET -isysroot $MOZ_FETCHES_DIR/MacOSX26.2.sdk"
+     EXE=
+     ;;
+ x86_64-pc-windows-gnu)
+     TARGET=x86_64-w64-mingw32
+     CC="x86_64-w64-mingw32-clang -DPKGCONFIG_IS_STATIC=1"
+diff --git a/taskcluster/scripts/misc/build-rust-based-toolchain.sh b/taskcluster/scripts/misc/build-rust-based-toolchain.sh
+--- a/taskcluster/scripts/misc/build-rust-based-toolchain.sh
++++ b/taskcluster/scripts/misc/build-rust-based-toolchain.sh
+@@ -40,11 +40,11 @@
+     if test "$TARGET" = "aarch64-apple-darwin"; then
+         export MACOSX_DEPLOYMENT_TARGET=11.0
+     else
+         export MACOSX_DEPLOYMENT_TARGET=10.15
+     fi
+-    MACOS_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.1.sdk
++    MACOS_SYSROOT=$MOZ_FETCHES_DIR/MacOSX26.2.sdk
+     export RUSTFLAGS="-Clinker=$MOZ_FETCHES_DIR/clang/bin/clang++ -C link-arg=-isysroot -C link-arg=$MACOS_SYSROOT -C link-arg=-fuse-ld=lld -C link-arg=--target=$TARGET $rust_lto_flags"
+     export CC="$MOZ_FETCHES_DIR/clang/bin/clang"
+     export CXX="$MOZ_FETCHES_DIR/clang/bin/clang++"
+     export TARGET_CFLAGS="-isysroot $MACOS_SYSROOT -fuse-ld=lld"
+     export TARGET_CXXFLAGS="-isysroot $MACOS_SYSROOT -fuse-ld=lld -stdlib=libc++"
+diff --git a/testing/mozharness/configs/openh264/macosx64-aarch64.py b/testing/mozharness/configs/openh264/macosx64-aarch64.py
+--- a/testing/mozharness/configs/openh264/macosx64-aarch64.py
++++ b/testing/mozharness/configs/openh264/macosx64-aarch64.py
+@@ -20,18 +20,18 @@
+     "arch": "aarch64",
+     "operating_system": "darwin",
+     "partial_env": {
+         "CFLAGS": (
+             "-target aarch64-apple-darwin -mcpu=apple-a12 "
+-            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.1.sdk "
++            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.2.sdk "
+             "-mmacosx-version-min=11.0".format(
+                 MOZ_FETCHES_DIR=os.environ["MOZ_FETCHES_DIR"]
+             )
+         ),
+         "LDFLAGS": (
+             "-target aarch64-apple-darwin -mcpu=apple-a12 "
+-            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.1.sdk "
++            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.2.sdk "
+             "-mmacosx-version-min=11.0".format(
+                 MOZ_FETCHES_DIR=os.environ["MOZ_FETCHES_DIR"]
+             )
+         ),
+         "PATH": (
+diff --git a/testing/mozharness/configs/openh264/macosx64.py b/testing/mozharness/configs/openh264/macosx64.py
+--- a/testing/mozharness/configs/openh264/macosx64.py
++++ b/testing/mozharness/configs/openh264/macosx64.py
+@@ -20,18 +20,18 @@
+     "arch": "x64",
+     "operating_system": "darwin",
+     "partial_env": {
+         "CXXFLAGS": (
+             "-target x86_64-apple-darwin "
+-            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.1.sdk "
++            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.2.sdk "
+             "-mmacosx-version-min=10.12".format(
+                 MOZ_FETCHES_DIR=os.environ["MOZ_FETCHES_DIR"]
+             )
+         ),
+         "LDFLAGS": (
+             "-target x86_64-apple-darwin "
+-            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.1.sdk "
++            "-isysroot {MOZ_FETCHES_DIR}/MacOSX26.2.sdk "
+             "-mmacosx-version-min=10.12".format(
+                 MOZ_FETCHES_DIR=os.environ["MOZ_FETCHES_DIR"]
+             )
+         ),
+         "PATH": (
+