diff -pruN 2.48.6-1/debian/changelog 2.48.6-1ubuntu2/debian/changelog
--- 2.48.6-1/debian/changelog	2025-09-04 08:33:59.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/changelog	2025-09-09 13:32:00.000000000 +0000
@@ -1,3 +1,16 @@
+webkit2gtk (2.48.6-1ubuntu2) questing; urgency=medium
+
+  * Fix FTBFS on RISC-V by manually disabling native SIMD (LP: #2121516)
+
+ -- Valentin Haudiquet <valentin.haudiquet@canonical.com>  Tue, 09 Sep 2025 15:32:00 +0200
+
+webkit2gtk (2.48.6-1ubuntu1) questing; urgency=medium
+
+  * Sync with Debian. Remaining change:
+    - Build with clang 19 on armhf instead of default clang 20
+
+ -- Jeremy Bícha <jbicha@ubuntu.com>  Thu, 04 Sep 2025 18:13:24 -0400
+
 webkit2gtk (2.48.6-1) unstable; urgency=medium
 
   [ Alberto Garcia ]
diff -pruN 2.48.6-1/debian/control 2.48.6-1ubuntu2/debian/control
--- 2.48.6-1/debian/control	2025-09-04 08:33:59.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/control	2025-09-04 22:13:24.000000000 +0000
@@ -2,7 +2,8 @@
 Source: webkit2gtk
 Priority: optional
 Section: web
-Maintainer: Debian WebKit Maintainers <pkg-webkit-maintainers@lists.alioth.debian.org>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+XSBC-Original-Maintainer: Debian WebKit Maintainers <pkg-webkit-maintainers@lists.alioth.debian.org>
 Uploaders: Gustavo Noronha Silva <kov@debian.org>,
            Emilio Pozuelo Monfort <pochu@debian.org>,
            Alberto Garcia <berto@igalia.com>
@@ -11,7 +12,8 @@ Build-Depends: debhelper-compat (= 13),
                bubblewrap [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
                xdg-dbus-proxy [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
                libseccomp-dev [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
-               clang [amd64 arm64 armel armhf i386 ppc64el riscv64 s390x],
+               clang [amd64 arm64 armel i386 ppc64el riscv64 s390x],
+               clang-19 [armhf],
                cmake (>= 3.20),
                flite1-dev,
                libglib2.0-dev,
diff -pruN 2.48.6-1/debian/control.in 2.48.6-1ubuntu2/debian/control.in
--- 2.48.6-1/debian/control.in	2025-09-04 08:33:59.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/control.in	2025-09-04 22:13:24.000000000 +0000
@@ -1,7 +1,8 @@
 Source: webkit2gtk
 Priority: optional
 Section: web
-Maintainer: Debian WebKit Maintainers <pkg-webkit-maintainers@lists.alioth.debian.org>
+Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
+XSBC-Original-Maintainer: Debian WebKit Maintainers <pkg-webkit-maintainers@lists.alioth.debian.org>
 Uploaders: Gustavo Noronha Silva <kov@debian.org>,
            Emilio Pozuelo Monfort <pochu@debian.org>,
            Alberto Garcia <berto@igalia.com>
@@ -10,7 +11,8 @@ Build-Depends: debhelper-compat (= 13),
                bubblewrap [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
                xdg-dbus-proxy [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
                libseccomp-dev [amd64 arm64 armel armhf i386 mips64el ppc64el riscv64 s390x hppa ppc64 x32],
-               clang [amd64 arm64 armel armhf i386 ppc64el riscv64 s390x],
+               clang [amd64 arm64 armel i386 ppc64el riscv64 s390x],
+               clang-19 [armhf],
                cmake (>= 3.20),
                flite1-dev,
                libglib2.0-dev,
diff -pruN 2.48.6-1/debian/patches/fix-ftbfs-riscv64-simd.patch 2.48.6-1ubuntu2/debian/patches/fix-ftbfs-riscv64-simd.patch
--- 2.48.6-1/debian/patches/fix-ftbfs-riscv64-simd.patch	1970-01-01 00:00:00.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/patches/fix-ftbfs-riscv64-simd.patch	2025-09-09 13:32:00.000000000 +0000
@@ -0,0 +1,20 @@
+Description: Fix FTBFS on RISC-V by manually disabling native SIMD
+ Manually disable native SIMD on riscv64 to prevent FTBFS
+Author: Valentin Haudiquet <valentin.haudiquet@canonical.com>
+Last-Update: 2025-09-09
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/webkit2gtk/+bug/2121516
+---
+
+--- webkit2gtk-2.48.6.orig/Source/WTF/wtf/simde/arm/neon.h
++++ webkit2gtk-2.48.6/Source/WTF/wtf/simde/arm/neon.h
+@@ -31,6 +31,10 @@
+ #if !defined(SIMDE_ARM_NEON_H)
+ #define SIMDE_ARM_NEON_H
+ 
++#ifndef SIMDE_RISCV_V_NO_NATIVE
++#define SIMDE_RISCV_V_NO_NATIVE 1
++#endif
++
+ /* AUTOMATICALLY GENERATED FILE, DO NOT MODIFY */
+ /* b8e468a68a879f51c694791e17a4bff175d7cd5e */
+ /* :: Begin simde/arm/neon/types.h :: */
diff -pruN 2.48.6-1/debian/patches/series 2.48.6-1ubuntu2/debian/patches/series
--- 2.48.6-1/debian/patches/series	2025-09-04 08:33:59.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/patches/series	2025-09-09 13:32:00.000000000 +0000
@@ -2,3 +2,4 @@ fix-ftbfs-riscv64.patch
 fix-ftbfs-sparc64.patch
 fix-ftbfs-x32.patch
 disable-nvidia-dmabuf.patch
+fix-ftbfs-riscv64-simd.patch
diff -pruN 2.48.6-1/debian/rules 2.48.6-1ubuntu2/debian/rules
--- 2.48.6-1/debian/rules	2025-09-04 08:33:59.000000000 +0000
+++ 2.48.6-1ubuntu2/debian/rules	2025-09-04 22:13:24.000000000 +0000
@@ -39,11 +39,16 @@ endif
 
 # Skia strongly recommends using clang
 # https://skia.org/docs/user/build/#supported-and-preferred-compilers
-ifneq (,$(filter $(DEB_HOST_ARCH),amd64 arm64 armel armhf i386 ppc64el riscv64 s390x))
+ifneq (,$(filter $(DEB_HOST_ARCH),amd64 arm64 armel i386 ppc64el riscv64 s390x))
 	EXTRA_CMAKE_ARGUMENTS += \
 	   -DCMAKE_C_COMPILER=clang \
 	   -DCMAKE_CXX_COMPILER=clang++
 endif
+ifneq (,$(filter $(DEB_HOST_ARCH),armhf))
+	EXTRA_CMAKE_ARGUMENTS += \
+	   -DCMAKE_C_COMPILER=clang-19 \
+	   -DCMAKE_CXX_COMPILER=clang++-19
+endif
 
 # Sacrifice speed in order to make it more likely resource limits
 # won't be hit.
