diff --git a/src/test/docker/Dockerfile b/src/test/docker/Dockerfile
index 74653694b8d26a8e3a1d40e0a4078ddf20b952bd..0f7e3453faf37f6cd3dc7b1e518fcaaae701f89e 100644
--- a/src/test/docker/Dockerfile
+++ b/src/test/docker/Dockerfile
@@ -7,12 +7,11 @@ RUN apt-get update && \
     libfreetype6-dev liblcms2-dev libwebp-dev tcl8.6-dev tk8.6-dev python3-tk \
     libharfbuzz-dev libfribidi-dev libxcb1-dev \
     python3-pip screen libpam0g-dev unzip curl shunit2 \
-    python3-sphinx
 
 RUN apt-get install -y \
   libcairo2-dev
 
-RUN pip3 install javasphinx recommonmark sphinx-rtd-theme sphinxcontrib-plantuml sphinx-a4doc
+RUN pip3 install sphinx javasphinx recommonmark sphinx-rtd-theme sphinxcontrib-plantuml sphinx-a4doc
 
 # Alternative, if javasphinx fails because python3-sphinx is too recent:
 # (`_l` not found):