diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 189ef2f98..aeff996b4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -107,8 +107,6 @@ pages:
   stage: deploy
   script:
     - mkdir public
-    # We use Python 3.5 in the current Stretch-based image. See https://github.com/timvink/mkdocs-git-revision-date-localized-plugin/issues/3
-    - sed -i "s+print(f\"WARNING - plugin locale setting '{plugin_locale}' will overwrite mkdocs locale '{mkdocs_locale}'\")+print(\"WARNING - plugin locale setting will overwrite mkdocs locale\")+g" /usr/local/lib/python3.5/dist-packages/mkdocs_git_revision_date_localized_plugin/plugin.py
     - mkdocs build
     - mv site/* public/
     - mix deps.get
diff --git a/docker/tests/Dockerfile b/docker/tests/Dockerfile
index 767f5247c..f70520a41 100644
--- a/docker/tests/Dockerfile
+++ b/docker/tests/Dockerfile
@@ -1,7 +1,7 @@
 FROM elixir:latest
 LABEL maintainer="Thomas Citharel <tcit@tcit.fr>"
 
-ENV REFRESHED_AT=2019-12-15
+ENV REFRESHED_AT=2019-12-16
 RUN apt-get update -yq && apt-get install -yq build-essential inotify-tools postgresql-client git curl gnupg xvfb libgtk-3-dev libnotify-dev libgconf-2-4 libnss3 libxss1 libasound2 python3-pip
 RUN curl -sL https://deb.nodesource.com/setup_10.x | bash && apt-get install nodejs -yq
 RUN npm install -g yarn wait-on