diff --git a/tests/lcitool/refresh b/tests/lcitool/refresh
index e0da0d2de1..1fdd37440c 100755
--- a/tests/lcitool/refresh
+++ b/tests/lcitool/refresh
@@ -72,6 +72,7 @@ def generate_dockerfile(host, target, project="qemu", cross=None, trailer=None,
     cmd.extend([target, project])
 
     if trailer is not None:
+        trailer = trailer.strip() + "\n"
         trailer += "\n".join(add_user_mapping)
     else:
         trailer = "\n".join(add_user_mapping)
@@ -100,113 +101,113 @@ def generate_yaml(os, target, arch, trailer=None):
     generate(filename, cmd, trailer)
 
 
-alpine_extras = [
-    "# https://gitlab.alpinelinux.org/alpine/aports/-/issues/17463\n",
-    "RUN apk add clang19-libclang\n",
-]
+alpine_extras = r"""
+# https://gitlab.alpinelinux.org/alpine/aports/-/issues/17463
+RUN apk add clang19-libclang
+"""
 
 # Netmap still needs to be manually built as it is yet to be packaged
 # into a distro. We also add cscope and gtags which are used in the CI
 # test
-debian13_extras = [
-    "# netmap/cscope/global\n",
-    "RUN DEBIAN_FRONTEND=noninteractive eatmydata \\\n",
-    "  apt install -y --no-install-recommends \\\n",
-    "  cscope\\\n",
-    "  global\\\n",
-    "  linux-headers-generic\n",
-    "RUN git clone https://github.com/luigirizzo/netmap.git /usr/src/netmap\n",
-    "RUN cd /usr/src/netmap && git checkout v11.3\n",
-    "RUN cd /usr/src/netmap/LINUX && \\\n",
-    "  ./configure --no-drivers --no-apps \\\n",
-    "  --kernel-dir=$(ls -d /usr/src/linux-headers-*-$(dpkg --print-architecture)) \\\n",
-    "  && make install\n",
-    "ENV QEMU_CONFIGURE_OPTS=--enable-netmap\n"
-]
+debian13_extras = r"""
+# netmap/cscope/global
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+  apt install -y --no-install-recommends \
+  cscope\
+  global\
+  linux-headers-generic
+RUN git clone https://github.com/luigirizzo/netmap.git /usr/src/netmap
+RUN cd /usr/src/netmap && git checkout v11.3
+RUN cd /usr/src/netmap/LINUX && \
+  ./configure --no-drivers --no-apps \
+  --kernel-dir=$(ls -d /usr/src/linux-headers-*-$(dpkg --print-architecture)) \
+  && make install
+ENV QEMU_CONFIGURE_OPTS=--enable-netmap
+"""
 
 # Based on the hub.docker.com/library/rust Dockerfiles
-fedora_rustup_nightly_extras = [
-    "RUN dnf install -y wget\n",
-    "ENV RUSTUP_HOME=/usr/local/rustup CARGO_HOME=/usr/local/cargo\n",
-    "ENV RUSTC=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc\n",
-    "ENV RUSTDOC=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustdoc\n",
-    "ENV CARGO=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/cargo\n",
-    "RUN set -eux && \\\n",
-    "  rustArch='x86_64-unknown-linux-gnu' && \\\n",
-    "  rustupSha256='6aeece6993e902708983b209d04c0d1dbb14ebb405ddb87def578d41f920f56d' && \\\n",
-    '  url="https://static.rust-lang.org/rustup/archive/1.27.1/${rustArch}/rustup-init" && \\\n',
-    '  wget "$url" && \\\n',
-    '  echo "${rustupSha256} *rustup-init" | sha256sum -c - && \\\n',
-    "  chmod +x rustup-init && \\\n",
-    "  ./rustup-init -y --no-modify-path --profile default --default-toolchain nightly --default-host ${rustArch} && \\\n",
-    "  chmod -R a+w $RUSTUP_HOME $CARGO_HOME && \\\n",
-    "  /usr/local/cargo/bin/rustup --version && \\\n",
-    "  /usr/local/cargo/bin/rustup run nightly cargo --version && \\\n",
-    "  /usr/local/cargo/bin/rustup run nightly rustc --version && \\\n",
-    '  test "$CARGO" = "$(/usr/local/cargo/bin/rustup +nightly which cargo)" && \\\n',
-    '  test "$RUSTDOC" = "$(/usr/local/cargo/bin/rustup +nightly which rustdoc)" && \\\n',
-    '  test "$RUSTC" = "$(/usr/local/cargo/bin/rustup +nightly which rustc)"\n',
-    'ENV PATH=$CARGO_HOME/bin:$PATH\n',
-    'RUN /usr/local/cargo/bin/rustup run nightly cargo install --locked bindgen-cli\n',
-    'RUN $CARGO --list\n',
-]
+fedora_rustup_nightly_extras = r"""
+RUN dnf install -y wget
+ENV RUSTUP_HOME=/usr/local/rustup CARGO_HOME=/usr/local/cargo
+ENV RUSTC=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustc
+ENV RUSTDOC=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustdoc
+ENV CARGO=/usr/local/rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/cargo
+RUN set -eux && \
+  rustArch='x86_64-unknown-linux-gnu' && \
+  rustupSha256='6aeece6993e902708983b209d04c0d1dbb14ebb405ddb87def578d41f920f56d' && \
+  url="https://static.rust-lang.org/rustup/archive/1.27.1/${rustArch}/rustup-init" && \
+  wget "$url" && \
+  echo "${rustupSha256} *rustup-init" | sha256sum -c - && \
+  chmod +x rustup-init && \
+  ./rustup-init -y --no-modify-path --profile default --default-toolchain nightly --default-host ${rustArch} && \
+  chmod -R a+w $RUSTUP_HOME $CARGO_HOME && \
+  /usr/local/cargo/bin/rustup --version && \
+  /usr/local/cargo/bin/rustup run nightly cargo --version && \
+  /usr/local/cargo/bin/rustup run nightly rustc --version && \
+  test "$CARGO" = "$(/usr/local/cargo/bin/rustup +nightly which cargo)" && \
+  test "$RUSTDOC" = "$(/usr/local/cargo/bin/rustup +nightly which rustdoc)" && \
+  test "$RUSTC" = "$(/usr/local/cargo/bin/rustup +nightly which rustc)"
+ENV PATH=$CARGO_HOME/bin:$PATH
+RUN /usr/local/cargo/bin/rustup run nightly cargo install --locked bindgen-cli
+RUN $CARGO --list
+"""
 
-ubuntu2404_rust_extras = [
-    "ENV RUSTC=/usr/bin/rustc-1.83\n",
-    "ENV RUSTDOC=/usr/bin/rustdoc-1.83\n",
-    "ENV CARGO_HOME=/usr/local/cargo\n",
-    'ENV PATH=$CARGO_HOME/bin:$PATH\n',
-    "RUN DEBIAN_FRONTEND=noninteractive eatmydata \\\n",
-    "  apt install -y --no-install-recommends cargo\n",
-    'RUN cargo install --locked bindgen-cli\n',
-]
+ubuntu2404_rust_extras = r"""
+ENV RUSTC=/usr/bin/rustc-1.83
+ENV RUSTDOC=/usr/bin/rustdoc-1.83
+ENV CARGO_HOME=/usr/local/cargo
+ENV PATH=$CARGO_HOME/bin:$PATH
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+  apt install -y --no-install-recommends cargo
+RUN cargo install --locked bindgen-cli
+"""
 
-debian_all_test_cross_compilers = [
-    "# extras for cross and alternate toolchains\n",
-    "RUN DEBIAN_FRONTEND=noninteractive eatmydata \\\n",
-    "  apt install -y --no-install-recommends \\\n",
-    "  clang\\\n",
-    "  dpkg-dev\\\n",
-    "  gdb-multiarch\\\n",
-    "  libclang-rt-dev\n",
-    "ENV AVAILABLE_COMPILERS=\"\\\n",
-    "  gcc-aarch64-linux-gnu \\\n",
-    "  libc6-dev-arm64-cross \\\n",
-    "  gcc-arm-linux-gnueabihf \\\n",
-    "  libc6-dev-armhf-cross \\\n",
-    "  gcc-alpha-linux-gnu \\\n"
-    "  libc6.1-dev-alpha-cross \\\n"
-    "  gcc-mips-linux-gnu \\\n",
-    "  libc6-dev-mips-cross \\\n",
-    "  gcc-mips64-linux-gnuabi64 \\\n",
-    "  libc6-dev-mips64-cross \\\n",
-    "  gcc-mips64el-linux-gnuabi64 \\\n",
-    "  libc6-dev-mips64el-cross \\\n",
-    "  gcc-mipsel-linux-gnu \\\n",
-    "  libc6-dev-mipsel-cross \\\n",
-    "  gcc-powerpc64le-linux-gnu \\\n",
-    "  libc6-dev-ppc64el-cross \\\n",
-    "  gcc-riscv64-linux-gnu \\\n",
-    "  libc6-dev-riscv64-cross \\\n",
-    "  gcc-s390x-linux-gnu \\\n",
-    "  libc6-dev-s390x-cross\\\n",
-    "  gcc-sh4-linux-gnu \\\n",
-    "  libc6-dev-sh4-cross \\\n",
-    "  \"\n",
-    "RUN if dpkg-architecture -e amd64; then \\\n",
-    "  export AVAILABLE_COMPILERS=\"${AVAILABLE_COMPILERS} gcc-hppa-linux-gnu libc6-dev-hppa-cross\"; \\\n",
-    "  export AVAILABLE_COMPILERS=\"${AVAILABLE_COMPILERS} gcc-m68k-linux-gnu libc6-dev-m68k-cross\"; \\\n",
-    "  export AVAILABLE_COMPILERS=\"${AVAILABLE_COMPILERS} gcc-powerpc-linux-gnu libc6-dev-powerpc-cross\"; \\\n",
-    "  export AVAILABLE_COMPILERS=\"${AVAILABLE_COMPILERS} gcc-powerpc64-linux-gnu libc6-dev-ppc64-cross\"; \\\n",
-    "  export AVAILABLE_COMPILERS=\"${AVAILABLE_COMPILERS} gcc-sparc64-linux-gnu libc6-dev-sparc64-cross\"; \\\n",
-    "fi && \\\n",
-    "DEBIAN_FRONTEND=noninteractive eatmydata \\\n",
-    "apt install -y --no-install-recommends \\\n",
-    "${AVAILABLE_COMPILERS} && \\\n",
-    "dpkg-query --showformat '${Package}_${Version}_${Architecture}' --show > /packages.txt\n",
-    "ENV QEMU_CONFIGURE_OPTS=--disable-docs\n",
-    "ENV DEF_TARGET_LIST=aarch64-linux-user,alpha-linux-user,arm-linux-user,hppa-linux-user,i386-linux-user,m68k-linux-user,mips-linux-user,mips64-linux-user,mips64el-linux-user,mipsel-linux-user,ppc-linux-user,ppc64-linux-user,ppc64le-linux-user,riscv64-linux-user,s390x-linux-user,sh4-linux-user,sparc64-linux-user\n",
-]
+debian_all_test_cross_compilers = r"""
+# extras for cross and alternate toolchains
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+  apt install -y --no-install-recommends \
+  clang\
+  dpkg-dev\
+  gdb-multiarch\
+  libclang-rt-dev
+ENV AVAILABLE_COMPILERS="\
+  gcc-aarch64-linux-gnu \
+  libc6-dev-arm64-cross \
+  gcc-arm-linux-gnueabihf \
+  libc6-dev-armhf-cross \
+  gcc-alpha-linux-gnu \
+  libc6.1-dev-alpha-cross \
+  gcc-mips-linux-gnu \
+  libc6-dev-mips-cross \
+  gcc-mips64-linux-gnuabi64 \
+  libc6-dev-mips64-cross \
+  gcc-mips64el-linux-gnuabi64 \
+  libc6-dev-mips64el-cross \
+  gcc-mipsel-linux-gnu \
+  libc6-dev-mipsel-cross \
+  gcc-powerpc64le-linux-gnu \
+  libc6-dev-ppc64el-cross \
+  gcc-riscv64-linux-gnu \
+  libc6-dev-riscv64-cross \
+  gcc-s390x-linux-gnu \
+  libc6-dev-s390x-cross\
+  gcc-sh4-linux-gnu \
+  libc6-dev-sh4-cross \
+  "
+RUN if dpkg-architecture -e amd64; then \
+  export AVAILABLE_COMPILERS="${AVAILABLE_COMPILERS} gcc-hppa-linux-gnu libc6-dev-hppa-cross"; \
+  export AVAILABLE_COMPILERS="${AVAILABLE_COMPILERS} gcc-m68k-linux-gnu libc6-dev-m68k-cross"; \
+  export AVAILABLE_COMPILERS="${AVAILABLE_COMPILERS} gcc-powerpc-linux-gnu libc6-dev-powerpc-cross"; \
+  export AVAILABLE_COMPILERS="${AVAILABLE_COMPILERS} gcc-powerpc64-linux-gnu libc6-dev-ppc64-cross"; \
+  export AVAILABLE_COMPILERS="${AVAILABLE_COMPILERS} gcc-sparc64-linux-gnu libc6-dev-sparc64-cross"; \
+fi && \
+DEBIAN_FRONTEND=noninteractive eatmydata \
+apt install -y --no-install-recommends \
+${AVAILABLE_COMPILERS} && \
+dpkg-query --showformat '${Package}_${Version}_${Architecture}' --show > /packages.txt
+ENV QEMU_CONFIGURE_OPTS=--disable-docs
+ENV DEF_TARGET_LIST=aarch64-linux-user,alpha-linux-user,arm-linux-user,hppa-linux-user,i386-linux-user,m68k-linux-user,mips-linux-user,mips64-linux-user,mips64el-linux-user,mipsel-linux-user,ppc-linux-user,ppc64-linux-user,ppc64le-linux-user,riscv64-linux-user,s390x-linux-user,sh4-linux-user,sparc64-linux-user
+"""
 
 def cross_build(prefix, targets):
     conf = "ENV QEMU_CONFIGURE_OPTS=--cross-prefix=%s\n" % (prefix)
@@ -223,20 +224,20 @@ try:
     # Standard native builds
     #
     generate_dockerfile("alpine", "alpine-323",
-                        trailer="".join(alpine_extras))
+                        trailer=alpine_extras)
     generate_dockerfile("centos9", "centos-stream-9")
     generate_dockerfile("debian", "debian-13",
-                        trailer="".join(debian13_extras))
+                        trailer=debian13_extras)
     generate_dockerfile("fedora", "fedora-43")
     generate_dockerfile("opensuse-leap", "opensuse-leap-16")
     generate_dockerfile("ubuntu2404", "ubuntu-2404",
-                        trailer="".join(ubuntu2404_rust_extras))
+                        trailer=ubuntu2404_rust_extras)
 
     #
     # Non-fatal Rust-enabled build
     #
     generate_dockerfile("fedora-rust-nightly", "fedora-43",
-                        trailer="".join(fedora_rustup_nightly_extras))
+                        trailer=fedora_rustup_nightly_extras)
 
     #
     # Cross compiling builds
@@ -293,7 +294,7 @@ try:
     generate_dockerfile("debian-all-test-cross", "debian-13",
                         project="qemu-minimal",
                         enable_rust=False,
-                        trailer="".join(debian_all_test_cross_compilers))
+                        trailer=debian_all_test_cross_compilers)
 
     #
     # GitLab packages lists