From bd08a01fc808d31e8c3e4d20b19dd22bd225df4b Mon Sep 17 00:00:00 2001
From: Andrew Ferrazzutti <andrewf@element.io>
Date: Tue, 25 Mar 2025 09:58:40 -0400
Subject: [PATCH] Dockerfile: set package arch via APT config option (#18271)

---
 changelog.d/18271.docker | 1 +
 docker/Dockerfile        | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 changelog.d/18271.docker

diff --git a/changelog.d/18271.docker b/changelog.d/18271.docker
new file mode 100644
index 0000000000..fcb2ac1e00
--- /dev/null
+++ b/changelog.d/18271.docker
@@ -0,0 +1 @@
+Specify the architecture of installed packages via an APT config option, which is more reliable than appending package names with ":{arch}".
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 27125c4c0b..54aa355370 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -148,7 +148,7 @@ RUN \
   for arch in arm64 amd64; do \
     mkdir -p /tmp/debs-${arch} && \
     cd /tmp/debs-${arch} && \
-    apt-get download $(sed "s/$/:${arch}/" /tmp/pkg-list); \
+    apt-get -o APT::Architecture="${arch}" download $(cat /tmp/pkg-list); \
   done
 
 # Extract the debs for each architecture