diff --git a/app/build.sh b/app/build.sh
index 5bbe8f8163..faa0cee5e8 100755
--- a/app/build.sh
+++ b/app/build.sh
@@ -42,7 +42,7 @@ Options
  -f FILE             ZIP file to build from (cannot be used with -d)
  -t                  add devtools
  -p PLATFORMS        build for platforms PLATFORMS (m=Mac, w=Windows, l=Linux)
- -a ARCH             architecture to build (arm64, x64, i686, win32)
+ -a ARCH             architecture to build (arm64, x64, win32)
                      * Ignored for Mac (always universal)
                      * If omitted on Windows/Linux, all standard archs are built
  -c CHANNEL          use update channel CHANNEL
@@ -210,7 +210,7 @@ if [ $BUILD_LINUX == 1 ]; then
 	if [[ -n $arch ]]; then
 		check_xulrunner_hash l $(get_canonical_arch l $arch)
 	else
-		for _a in x64 arm64 i686; do
+		for _a in x64 arm64; do
 			check_xulrunner_hash l "$_a"
 		done
 	fi
@@ -296,7 +296,7 @@ elif [[ $BUILD_LINUX == 1 ]]; then
 	if [[ -n $arch ]]; then
 		omni_arch=$(get_canonical_arch l $arch)
 	else
-		for cand in x86_64 arm64 i686; do
+		for cand in x86_64 arm64; do
 			[[ -d "${LINUX_RUNTIME_PATH_PREFIX}${cand}" ]] && { omni_arch="$cand"; break; }
 		done
 	fi
@@ -1119,7 +1119,7 @@ if [ $BUILD_LINUX == 1 ]; then
 	if [[ -n $arch ]]; then
 		archs=("$(get_canonical_arch l $arch)")
 	else
-		archs=(x64 arm64 i686)
+		archs=(x64 arm64)
 	fi
 	for arch in "${archs[@]}"; do
 		[[ $arch == x64 ]] && arch="x86_64"
diff --git a/app/scripts/dir_build b/app/scripts/dir_build
index ec2bad7ea2..4a815f2ed1 100755
--- a/app/scripts/dir_build
+++ b/app/scripts/dir_build
@@ -16,7 +16,7 @@ Architecture is ignored for Mac builds, which are always shipped as universal bi
 
 Options
  -p PLATFORM        Platform to build (m=Mac, w=Windows, l=Linux)
- -a ARCH            Target architecture (arm64, x64, i686, win32) — **Windows/Linux only**
+ -a ARCH            Target architecture (arm64, x64, win32) — **Windows/Linux only**
  -t                 add devtools
  -f                 force a full rebuild instead of updating the staged build in place
 DONE
@@ -79,7 +79,6 @@ else
 		case "$(uname -m)" in
 			arm64|aarch64) arch="arm64" ;;
 			x86_64)         arch="x64"   ;;
-			i?86)           arch="i686"  ;;
 		esac
 	fi
 fi
diff --git a/app/scripts/fetch_xulrunner b/app/scripts/fetch_xulrunner
index b48aa9ae68..b01afa3d63 100755
--- a/app/scripts/fetch_xulrunner
+++ b/app/scripts/fetch_xulrunner
@@ -35,7 +35,7 @@ Required
 Optional / Conditional
  -a ARCH       - Mac:      disallowed (builds are universal)
                - Windows:  x64 | arm64 | win32
-               - Linux:    x64 (or x86_64) | arm64 | i686
+               - Linux:    x64 (or x86_64) | arm64
                If omitted on Windows/Linux, all standard archs are fetched.
 DONE
 	exit 1
@@ -87,7 +87,7 @@ if [[ $BUILD_WIN == 1 || $BUILD_LINUX == 1 ]]; then
 		fi
 		if [[ $BUILD_LINUX == 1 ]]; then
 			[[ $arch == x64 ]] && arch="x86_64"
-			case $arch in x86_64|i686|arm64) ;; *) echo "Invalid Linux arch: $arch" >&2; echo; usage;; esac
+			case $arch in x86_64|arm64) ;; *) echo "Invalid Linux arch: $arch" >&2; echo; usage;; esac
 		fi
 	fi
 fi
@@ -769,7 +769,7 @@ if [ $BUILD_LINUX == 1 ]; then
 	if [[ -n $arch ]]; then
 		arch_list=("$arch")
 	else
-		arch_list=(x86_64 arm64 i686)
+		arch_list=(x86_64 arm64)
 	fi
 	for arch in "${arch_list[@]}"; do
 		xdir="firefox-linux-$arch"
diff --git a/app/scripts/xulrunner_hash b/app/scripts/xulrunner_hash
index bad24f5264..aec7662205 100755
--- a/app/scripts/xulrunner_hash
+++ b/app/scripts/xulrunner_hash
@@ -8,7 +8,7 @@
 #   * **Windows (w)** ‑a is **required**. Accepted values:
 #         win32 | x64 | arm64
 #   * **Linux (l)**   ‑a is **required**. Accepted values:
-#         x86_64 | i686 | arm64 (alias x64 → x86_64)
+#         x86_64 | arm64 (alias x64 → x86_64)
 
 set -euo pipefail
 
@@ -26,7 +26,7 @@ Usage: xulrunner_hash.sh -p <m|w|l> [-a ARCH]
  -p PLATFORM   m (mac), w (windows), l (linux)        [required]
  -a ARCH       *required* for Windows & Linux builds
                Windows:  x64 | arm64 | win32
-               Linux:    x64 (or x86_64) | arm64 | i686
+               Linux:    x64 (or x86_64) | arm64
                Mac:      disallowed – always universal
 DONE
 	exit 1
@@ -65,7 +65,7 @@ case $platform in
 		[[ -z $arch ]] && { echo "-a is required for Linux builds" >&2; echo; usage; }
 		[[ $arch == x64 ]] && arch="x86_64"
 		case $arch in
-			x86_64|i686|arm64) ;;
+			x86_64|arm64) ;;
 			*) echo "Invalid Linux arch: $arch" >&2; echo; usage;;
 		esac
 		GECKO_VERSION="$GECKO_VERSION_LINUX"