diff --git a/firefox/build b/firefox/build
index 845149e..738ec5a 100755
--- a/firefox/build
+++ b/firefox/build
@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
 # Docker build
 # Optional buildtag
-DOCKER_BUILDKIT=1 docker build . \
+DOCKER_BUILDKIT=1 \
+docker build . \
+    --build-arg debug=${debug:-""} \
     --tag ${buildtag:-alpine/firefox}