diff --git a/README.md b/README.md
index 90ebf33..21d548b 100644
--- a/README.md
+++ b/README.md
@@ -409,3 +409,13 @@ The tests execute the FreeBSD run template under the host's POSIX shell with
 fixture build/test commands and real tar archives. They cover failures in each
 custom test group, default build/test failures, missing/corrupt packages and font
 environment propagation. They do not replace native FreeBSD caller runs.
+
+
+## Linux portal build prerequisite
+
+The native and RISC-V cross-compilation dependency actions install libdbus
+headers for the target architecture. Applications that opt into native Wayland
+file-portal support through libdbus can then build on clean runners. This only
+adds build dependencies; it does not enable a feature, change app permissions or
+alter the release dependency graph. Native apt installation and RISC-V linking
+still need validation on the corresponding CI runners.
diff --git a/actions/install-linux-deps/action.yml b/actions/install-linux-deps/action.yml
index 9e32341..88d7ae6 100644
--- a/actions/install-linux-deps/action.yml
+++ b/actions/install-linux-deps/action.yml
@@ -20,7 +20,7 @@ runs:
         sudo apt-get update
         sudo apt-get install -y --no-install-recommends \
           libxkbcommon-dev libwayland-dev libx11-dev libxrandr-dev libxi-dev libgl1-mesa-dev \
-          libasound2-dev pkg-config \
+          libasound2-dev libdbus-1-dev pkg-config \
           desktop-file-utils appstream python3-yaml zsync
 
     - uses: storytold/craft-common-actions/actions/install-nfpm@main
diff --git a/actions/install-riscv64-cross/action.yml b/actions/install-riscv64-cross/action.yml
index a900c34..9bbf07e 100644
--- a/actions/install-riscv64-cross/action.yml
+++ b/actions/install-riscv64-cross/action.yml
@@ -30,5 +30,5 @@ runs:
         sudo apt-get install -y --no-install-recommends \
           gcc-riscv64-linux-gnu binutils-riscv64-linux-gnu libc6-dev-riscv64-cross libc6-dev:riscv64 qemu-user \
           libxkbcommon-dev:riscv64 libwayland-dev:riscv64 libx11-dev:riscv64 libxrandr-dev:riscv64 \
-          libxi-dev:riscv64 libgl1-mesa-dev:riscv64 libasound2-dev:riscv64 pkg-config \
+          libxi-dev:riscv64 libgl1-mesa-dev:riscv64 libasound2-dev:riscv64 libdbus-1-dev:riscv64 pkg-config \
           desktop-file-utils appstream