diff --git a/etc/taskcluster/docker/build.dockerfile b/etc/taskcluster/docker/build.dockerfile
index dea5112e268..c5e148c4df3 100644
--- a/etc/taskcluster/docker/build.dockerfile
+++ b/etc/taskcluster/docker/build.dockerfile
@@ -11,6 +11,9 @@ RUN \
         make \
         cmake \
         #
+        # Fontconfig
+        gperf \
+        #
         # ANGLE
         xorg-dev \
         #