diff --git a/Dockerfile.dev b/Dockerfile.dev
index 40f281b95ebd2f..0eb9c42c11d914 100644
--- a/Dockerfile.dev
+++ b/Dockerfile.dev
@@ -1,10 +1,10 @@
 FROM python:3.8
 
-RUN \
+RUN true \
     && apt-get update && apt-get install -y --no-install-recommends \
         software-properties-common \
-    && add-apt-repository ppa:jonathonf/ffmpeg-4 \
-    && apt-get update && apt-get install -y --no-install-recommends \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends \
         libudev-dev \
         libavformat-dev \
         libavcodec-dev \
diff --git a/azure-pipelines-ci.yml b/azure-pipelines-ci.yml
index d620cd14594237..d9b9f9a3d2d7c5 100644
--- a/azure-pipelines-ci.yml
+++ b/azure-pipelines-ci.yml
@@ -121,7 +121,16 @@ stages:
               . venv/bin/activate
               pre-commit run black --all-files --show-diff-on-failure
             displayName: "Check Black formatting"
-
+      - job: "ValidateDockerfiles"
+        pool:
+          vmImage: "ubuntu-latest"
+        steps:
+          - task: Docker@2
+            displayName: Build Dockerfile.dev
+            inputs:
+              repository: homeassistant-dev
+              command: build
+              Dockerfile: Dockerfile.dev
   - stage: "Tests"
     dependsOn:
       - "Overview"