diff --git a/.travis.yml b/.travis.yml
index 3b53acd7859c56ff0713cc72f9c4a06cc00ffa29..c9c170e8b9280866f9c4e09780570a966c63f9f1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -32,4 +32,4 @@ install:
 
 script:
   - cd "$TRAVIS_BUILD_DIR"
-  - bash ./tools/scripts/travis_tests.sh
+  - env -i bash ./tools/scripts/travis_tests.sh
diff --git a/Vagrantfile b/Vagrantfile
index 6ef3dd7944623f1d80035dd5cb2d900f566b8735..a5061cbc752f3697a80452c1ee532a3acded207e 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -26,12 +26,17 @@ Vagrant.configure(2) do |config|
 
     chown -R vagrant.vagrant /home/vagrant/lisa
 
+    # Let' use a venv local to vagrant so that we don't pollute the host one.
+    # This allows to use LISA both from the host and the VM.
+    export LISA_VENV_PATH=/home/vagrant/venv
+
     # .bashrc setup
     echo "cd /home/vagrant/lisa" >> /home/vagrant/.bashrc
     for LC in $(locale | cut -d= -f1);
     do
         echo unset $LC  >> /home/vagrant/.bashrc
     done
+    echo 'export LISA_VENV_PATH=$LISA_VENV_PATH' >> /home/vagrant/.bashrc
     echo 'source init_env' >> /home/vagrant/.bashrc
 
     # Trigger the creation of a venv
diff --git a/init_env b/init_env
index e908781dbb70ca6bd597fce142fb12431bff82ba..d054389a86d24438debbf49565762b45ddaade06 100644
--- a/init_env
+++ b/init_env
@@ -20,6 +20,14 @@
 
 _lisa_shell_ret=1
 
+# Ensure we aleays start from a clean new shell
+if [[ -n $LISA_HOME ]]; then
+	echo
+	echo "ERROR: Please source init_env from a fresh new shell."
+	echo
+	return
+fi
+
 setup_paths() {
 	# Bail out if local tools are not installed
 	[[ -d $LISA_HOME/tools/android-sdk-linux ]] || return
diff --git a/install_base_ubuntu.sh b/install_base_ubuntu.sh
index ada1553778f7e8e58ab1dff4555e3435c2898f67..71c8ac247fa088072e0704bc0c5561eb09d3aefb 100755
--- a/install_base_ubuntu.sh
+++ b/install_base_ubuntu.sh
@@ -42,6 +42,16 @@ install_sdk() {
     fi
 }
 
+install_nodejs() {
+    # NodeJS v8+ is required, Ubuntu 16.04 LTS supports only an older version.
+    # As a special case we can install it as a snap package
+    if grep 16.04 /etc/lsb-release >/dev/null; then
+        sudo snap install node --classic --channel=8
+        return
+    fi
+    sudo apt-get install -y nodejs npm
+}
+
 set -eu
 
 install_android_sdk=n
@@ -64,6 +74,10 @@ apt-get -y install build-essential git wget expect kernelshark \
 	python3 python3-pip python3-venv python3-tk gobject-introspection \
 	libcairo2-dev libgirepository1.0-dev gir1.2-gtk-3.0
 
+install_nodejs
+
 if [ "$install_android_sdk" == y ]; then
     install_sdk
 fi
+
+# vim: set tabstop=4 shiftwidth=4 textwidth=80 expandtab:
diff --git a/setup.py b/setup.py
index b8f724f79e7486d8ae01f05e31ef858fc31fd2c2..f24ca6067cae4d02534e08aa2de0ed21270bd7cf 100755
--- a/setup.py
+++ b/setup.py
@@ -104,7 +104,8 @@ setup(
     extras_require={
         "notebook": [
             "ipython",
-            "jupyterlab"
+            "jupyterlab",
+            "ipywidgets",
         ],
 
         "doc": [
diff --git a/shell/lisa_shell b/shell/lisa_shell
index 712609de6ac92c3dc2dc23216009bf7ae53bbab9..57b62c9aa2b8d487396f083e63fead8a5767b71c 100755
--- a/shell/lisa_shell
+++ b/shell/lisa_shell
@@ -154,6 +154,22 @@ function _lisa-upgrade-pip {
     fi
 }
 
+function _lisa-install-nbextensions {
+    which jupyter &>/dev/null || return
+    if which node &>/dev/null; then
+        echo
+        echo "Enabling ipywidget extensions..."
+        jupyter labextension install @jupyter-widgets/jupyterlab-manager
+        return
+    fi
+
+    # If NodeJS is still not available, we just warn the user
+    echo
+    echo "NOTE: Missing NodeJS support!"
+    echo "Install it on your system and run lisa-install "
+    echo "again if you want to enable ipywidgets support."
+}
+
 function lisa-install {
     # Check that some prerequisites are available on the system, since they
     # cannot be installed using pip in a venv
@@ -196,6 +212,9 @@ function lisa-install {
     # Make sure the shell has taken into account the new content of directories
     # listed in $PATH.
     _lisa-reload-PATH
+
+    # Install additiona Jupyter Notebook extensions
+    _lisa-install-nbextensions
 }
 
 ################################################################################
@@ -403,6 +422,9 @@ EOF
 # LISA Shell MAIN
 ################################################################################
 
+# Activate the venv unless it was explicitely disabled
+lisa-venv-activate
+
 # Dump out a nice LISA Shell logo
 clear
 echo -e "$LISASHELL_BANNER"
@@ -418,8 +440,13 @@ Welcome to the Linux Integrated System Analysis SHELL!
 LISA version   : $(git rev-parse --short=11 HEAD)
 python version : $PYTHON_VERSION
 LISA_HOME      : $LISA_HOME
+
 EOF
 
+if which jupyter >/dev/null; then
+    jupyter labextension list
+fi
+
 cat <<EOF
 
 
@@ -430,7 +457,4 @@ EOF
 # Setup default SHELL text color
 echo -e "$LISASHELL_DEFAULT"
 
-# Activate the venv unless it was explicitely disabled
-lisa-venv-activate
-
-# vim :set tabstop=4 shiftwidth=4 textwidth=80 expandtab
+# vim: set tabstop=4 shiftwidth=4 textwidth=80 expandtab: