docuseal: use DocuSeal's patched PDFium build to fix service start

DocuSeal switched to its own PDFium fork (upstream commit "adjust pdfium",
2026-08-15) and now attaches functions that only exist in that build, e.g.
FPDFPage_GetAnnotCountRaw from the added fpdf_annots_raw.h. The generic
bblanchon/pdfium-binaries library the script installed does not export them,
so lib/pdfium.rb raises FFI::NotFoundError while Rails eager-loads and both
docuseal.service and docuseal-sidekiq.service fail to start:

  Unable to load application: FFI::NotFoundError: Function
  'FPDFPage_GetAnnotCountRaw' not found in [libpdfium.so]

Install the library from docusealco/pdfium-binaries instead, matching the
upstream Dockerfile. It is only published as a musl build (DocuSeal's image is
Alpine based), so the musl runtime is installed and its library directory is
added to the loader search path - the shared object needs "libc.so" (musl) at
dlopen time. Verified on glibc: the library loads, resolves the raw annotation
functions and renders pages correctly.

The update path now refreshes PDFium too, so existing containers are repaired
by running "update" even when DocuSeal itself is already up to date.

ct/docuseal.sh

@@ -30,6 +30,18 @@ function update_script() {
     exit
   fi
 
+  ensure_dependencies musl
+  [[ -f /opt/pdfium/lib/libpdfium.so ]] || rm -f "$HOME/.pdfium"
+  fetch_and_deploy_gh_release "pdfium" "docusealco/pdfium-binaries" "prebuild" "latest" "/opt/pdfium" "pdfium-musl-$(uname -m).zip"
+  if ! cmp -s /opt/pdfium/lib/libpdfium.so /usr/lib/libpdfium.so; then
+    msg_info "Updating PDFium"
+    install -m 644 /opt/pdfium/lib/libpdfium.so /usr/lib/libpdfium.so
+    echo "/usr/lib/$(uname -m)-linux-musl" >/etc/ld.so.conf.d/musl.conf
+    $STD ldconfig
+    systemctl restart docuseal docuseal-sidekiq 2>/dev/null || true
+    msg_ok "Updated PDFium"
+  fi
+
   if check_for_gh_release "docuseal" "docusealco/docuseal"; then
     msg_info "Stopping Services"
     systemctl stop docuseal docuseal-sidekiq

install/docuseal-install.sh

@@ -29,16 +29,16 @@ $STD apt install -y \
   libvips-dev \
   libheif1 \
   redis-server \
-  fontconfig
+  fontconfig \
+  musl
 msg_ok "Installed Dependencies"
 
 NODE_VERSION="22" NODE_MODULE="yarn" setup_nodejs
 PG_VERSION="17" setup_postgresql
 PG_DB_NAME="docuseal" PG_DB_USER="docuseal" setup_postgresql_db
 
-msg_info "Downloading Fonts and PDFium"
+msg_info "Downloading Fonts"
 mkdir -p /opt/fonts /usr/share/fonts/noto
-ARCH=$(uname -m | sed 's/x86_64/x64/;s/aarch64/arm64/')
 curl -fsSL -o /opt/fonts/GoNotoKurrent-Regular.ttf \
   https://github.com/satbyy/go-noto-universal/releases/download/v7.0/GoNotoKurrent-Regular.ttf
 curl -fsSL -o /opt/fonts/GoNotoKurrent-Bold.ttf \
@@ -48,12 +48,15 @@ curl -fsSL -o /opt/fonts/DancingScript-Regular.otf \
 ln -sf /opt/fonts/GoNotoKurrent-Regular.ttf /usr/share/fonts/noto/
 ln -sf /opt/fonts/GoNotoKurrent-Bold.ttf /usr/share/fonts/noto/
 $STD fc-cache -f
-curl -fsSL -o /tmp/pdfium.tgz \
-  "https://github.com/bblanchon/pdfium-binaries/releases/latest/download/pdfium-linux-${ARCH}.tgz"
-mkdir -p /tmp/pdfium && tar -xzf /tmp/pdfium.tgz -C /tmp/pdfium
-cp /tmp/pdfium/lib/libpdfium.so /usr/lib/libpdfium.so
-rm -rf /tmp/pdfium /tmp/pdfium.tgz
-msg_ok "Downloaded Fonts and PDFium"
+msg_ok "Downloaded Fonts"
+
+fetch_and_deploy_gh_release "pdfium" "docusealco/pdfium-binaries" "prebuild" "latest" "/opt/pdfium" "pdfium-musl-$(uname -m).zip"
+
+msg_info "Installing PDFium"
+install -m 644 /opt/pdfium/lib/libpdfium.so /usr/lib/libpdfium.so
+echo "/usr/lib/$(uname -m)-linux-musl" >/etc/ld.so.conf.d/musl.conf
+$STD ldconfig
+msg_ok "Installed PDFium"
 
 fetch_and_deploy_gh_release "docuseal" "docusealco/docuseal" "tarball"