diff --git a/Makefile b/Makefile
index 960a1d63fa..d683bf3f9e 100644
--- a/Makefile
+++ b/Makefile
@@ -87,4 +87,4 @@ test/%: ## run tests against a stack
 	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test
 
 test/base-notebook: ## test supported options in the base notebook
-	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test base-notebook/test
\ No newline at end of file
+	@TEST_IMAGE="$(OWNER)/$(notdir $@)" pytest test base-notebook/test
diff --git a/base-notebook/Dockerfile b/base-notebook/Dockerfile
index 1146aff3a8..80a0e48ef0 100644
--- a/base-notebook/Dockerfile
+++ b/base-notebook/Dockerfile
@@ -1,9 +1,9 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 
-# Ubuntu 18.04 (bionic) from 2018-05-26
-# https://github.com/docker-library/official-images/commit/aac6a45b9eb2bffb8102353c350d341a410fb169
-ARG BASE_CONTAINER=ubuntu:bionic-20180526@sha256:c8c275751219dadad8fa56b3ac41ca6cb22219ff117ca98fe82b42f24e1ba64e
+# Ubuntu 18.04 (bionic) from 2019-06-12
+# https://github.com/tianon/docker-brew-ubuntu-core/commit/3c462555392cb188830b7c91e29311b5fad90cfe
+ARG BASE_CONTAINER=ubuntu:bionic-20190612@sha256:9b1702dcfe32c873a770a32cfd306dd7fc1c4fd134adfb783db68defc8894b3c
 FROM $BASE_CONTAINER
 
 LABEL maintainer="Jupyter Project <jupyter@googlegroups.com>"
@@ -60,18 +60,19 @@ RUN echo "auth requisite pam_deny.so" >> /etc/pam.d/su && \
     fix-permissions "$(dirname $CONDA_DIR)"
 
 USER $NB_UID
+WORKDIR $HOME
 
 # Setup work directory for backward-compatibility
 RUN mkdir /home/$NB_USER/work && \
     fix-permissions /home/$NB_USER
 
 # Install conda as jovyan and check the md5 sum provided on the download site
-ENV MINICONDA_VERSION=4.5.12 \
-    CONDA_VERSION=4.6.14
+ENV MINICONDA_VERSION=4.6.14 \
+    CONDA_VERSION=4.7.5
 
 RUN cd /tmp && \
     wget --quiet https://repo.continuum.io/miniconda/Miniconda3-${MINICONDA_VERSION}-Linux-x86_64.sh && \
-    echo "866ae9dff53ad0874e1d1a60b1ad1ef8 *Miniconda3-${MINICONDA_VERSION}-Linux-x86_64.sh" | md5sum -c - && \
+    echo "718259965f234088d785cad1fbd7de03 *Miniconda3-${MINICONDA_VERSION}-Linux-x86_64.sh" | md5sum -c - && \
     /bin/bash Miniconda3-${MINICONDA_VERSION}-Linux-x86_64.sh -f -b -p $CONDA_DIR && \
     rm Miniconda3-${MINICONDA_VERSION}-Linux-x86_64.sh && \
     echo "conda ${CONDA_VERSION}" >> $CONDA_DIR/conda-meta/pinned && \
@@ -111,10 +112,7 @@ RUN conda install --quiet --yes \
     fix-permissions $CONDA_DIR && \
     fix-permissions /home/$NB_USER
 
-USER root
-
 EXPOSE 8888
-WORKDIR $HOME
 
 # Configure container startup
 ENTRYPOINT ["tini", "-g", "--"]
@@ -125,6 +123,9 @@ COPY start.sh /usr/local/bin/
 COPY start-notebook.sh /usr/local/bin/
 COPY start-singleuser.sh /usr/local/bin/
 COPY jupyter_notebook_config.py /etc/jupyter/
+
+# Fix permissions on /etc/jupyter as root
+USER root
 RUN fix-permissions /etc/jupyter/
 
 # Switch back to jovyan to avoid accidental container runs as root
diff --git a/scipy-notebook/Dockerfile b/scipy-notebook/Dockerfile
index 88dda7ec65..362c1529cc 100644
--- a/scipy-notebook/Dockerfile
+++ b/scipy-notebook/Dockerfile
@@ -15,8 +15,6 @@ RUN apt-get update && \
 USER $NB_UID
 
 # Install Python 3 packages
-# Remove pyqt and qt pulled in for matplotlib since we're only ever going to
-# use notebook-friendly backends in these images
 RUN conda install --quiet --yes \
     'conda-forge::blas=*=openblas' \
     'ipywidgets=7.5*' \
@@ -43,7 +41,6 @@ RUN conda install --quiet --yes \
     'beautifulsoup4=4.7.*' \
     'protobuf=3.7.*' \
     'xlrd'  && \
-    conda remove --quiet --yes --force qt pyqt && \
     conda clean --all -f -y && \
     # Activate ipywidgets extension in the environment that runs the notebook server
     jupyter nbextension enable --py widgetsnbextension --sys-prefix && \