diff --git a/.dockerignore b/.dockerignore
index 4dcc4dd58..e1fef8e0a 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -1,4 +1,24 @@
-.git
+# Copyright (c) 2016-2020 Martin Donath <martin.donath@squidfunk.com>
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to
+# deal in the Software without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+# sell copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+# IN THE SOFTWARE.
+
+.git
 .github
 docs
 node_modules
diff --git a/Dockerfile b/Dockerfile
index 255d4877f..5abc28421 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -41,7 +41,7 @@ RUN \
   && rm -rf /tmp/* \
   && pip install --no-cache-dir \
     'mkdocs-minify-plugin>=0.2' \
-    'mkdocs-git-revision-date-localized-plugin'
+    'mkdocs-git-revision-date-localized-plugin>=0.4'
 
 # Set working directory
 WORKDIR /docs