diff --git a/functions/packages.sh b/functions/packages.sh
index 9e25df5f3..2481edc25 100755
--- a/functions/packages.sh
+++ b/functions/packages.sh
@@ -145,3 +145,28 @@ Check_installed ()
 	fi
 }
 
+# $1 = Packagename
+# Echoes:
+#  1 if the package is available
+#  0 otherwise
+Check_package_available ()
+{
+	local _PACKAGE="${1}"
+
+	if [ "${LB_BUILD_WITH_CHROOT}" = "true" ]
+	then
+		if [ $(Chroot chroot apt-cache show "^${_PACKAGE}$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
+		then
+			echo 1
+			return
+		fi
+	else
+		if [ $(apt-cache show "^${_PACKAGE}$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
+		then
+			echo 1
+			return
+		fi
+	fi
+	echo 0
+}
+
diff --git a/scripts/build/chroot_firmware b/scripts/build/chroot_firmware
index 4d8613fdf..d198ba267 100755
--- a/scripts/build/chroot_firmware
+++ b/scripts/build/chroot_firmware
@@ -54,17 +54,9 @@ Check_package host /usr/bin/wget wget
 FIRMWARE_PACKAGES=""
 
 # Manually add firmware-linux meta package if available
-if [ "${LB_BUILD_WITH_CHROOT}" = "true" ]
+if [ $(Check_package_available "firmware-linux") -eq 1 ]
 then
-	if [ $(Chroot chroot apt-cache show "^firmware-linux$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
-	then
-		FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
-	fi
-else
-	if [ $(apt-cache show "^firmware-linux$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
-	then
-		FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
-	fi
+	FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
 fi
 
 Firmware_List_From_Contents "${LB_PARENT_MIRROR_CHROOT}" "${LB_PARENT_DISTRIBUTION_CHROOT}" "${LB_PARENT_ARCHIVE_AREAS}"
diff --git a/scripts/build/installer_debian-installer b/scripts/build/installer_debian-installer
index 5045741d5..22ea61e6b 100755
--- a/scripts/build/installer_debian-installer
+++ b/scripts/build/installer_debian-installer
@@ -380,7 +380,26 @@ then
 
 	case "${LB_ARCHITECTURE}" in
 		amd64)
-			DI_REQ_PACKAGES="grub-pc grub-common libefiboot1 libefiboot1t64 libefivar1 libefivar1t64 libfuse2 libfuse2t64 libfuse3-3" # BIOS
+			DI_REQ_PACKAGES="grub-pc grub-common libfuse3-3" # BIOS
+			# Starting in trixie, the t64-packages have a 64-bit timestamp
+			if [ $(Check_package_available "libefiboot1t64") -eq 1 ]
+			then
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libefiboot1t64"
+			else
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libefiboot1"
+			fi
+			if [ $(Check_package_available "libefivar1t64") -eq 1 ]
+			then
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libefivar1t64"
+			else
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libefivar1"
+			fi
+			if [ $(Check_package_available "libfuse2t64") -eq 1 ]
+			then
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libfuse2t64"
+			else
+				DI_REQ_PACKAGES="${DI_REQ_PACKAGES} libfuse2"
+			fi
 			DI_REQ_PACKAGES="${DI_REQ_PACKAGES} grub-efi-amd64 efibootmgr grub-efi-amd64-signed shim-signed" # UEFI (required for d-i, includes suggested packages)
 			DI_REQ_PACKAGES="${DI_REQ_PACKAGES} efibootmgr grub-efi-amd64 grub-efi-amd64-bin grub-efi-amd64-signed grub2-common mokutil shim-helpers-amd64-signed shim-signed shim-signed-common shim-unsigned cryptsetup cryptsetup-initramfs keyutils" # UEFI (required by Calamares)
 			DI_PACKAGES="linux-image-amd64"
@@ -417,17 +436,9 @@ then
 		FIRMWARE_PACKAGES=""
 
 		# Manually add firmware-linux meta package if available
-		if [ "${LB_BUILD_WITH_CHROOT}" = "true" ]
+		if [ $(Check_package_available "firmware-linux") -eq 1 ]
 		then
-			if [ $(Chroot chroot apt-cache show "^firmware-linux$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
-			then
-				FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
-			fi
-		else
-			if [ $(apt-cache show "^firmware-linux$" 2> /dev/null | grep "^Package:" | wc -l) -eq 1 ]
-			then
-				FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
-			fi
+			FIRMWARE_PACKAGES="${FIRMWARE_PACKAGES} firmware-linux"
 		fi
 
 		Firmware_List_From_Contents "${LB_PARENT_MIRROR_CHROOT}" "${LB_PARENT_DISTRIBUTION_CHROOT}" "${LB_PARENT_ARCHIVE_AREAS}"