diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 84b3027a80d761e51cd2fdcc0dcf0fb2e29160a1..1a70c1875f41da7168824391509596c6bdeb859d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -63,133 +63,6 @@ pages:
 before_script:
   - export MPLBACKEND="agg"
 
-run_critical_filtering:
-  stage: demo_runs
-  script:
-    - ls
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/critical_filtering.py
-    - python3 demos/critical_filtering.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_nonlinear_critical_filter:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/nonlinear_critical_filter.py
-    - python3 demos/nonlinear_critical_filter.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_nonlinear_wiener_filter:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/nonlinear_wiener_filter.py
-    - python3 demos/nonlinear_wiener_filter.py
-  only:
-    - run_demos
-  artifacts:
-    paths:
-      - '*.png'
-
-# FIXME: disable for now. Fixing it is part of issue #244.
-#run_poisson_demo:
-#  stage: demo_runs
-#  script:
-#    - python setup.py install --user -f
-#    - python3 setup.py install --user -f
-#    - python demos/poisson_demo.py
-#    - python3 demos/poisson_demo.py
-#  artifacts:
-#    paths:
-#      - '*.png'
-
-run_probing:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/probing.py
-    - python3 demos/probing.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_sampling:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/sampling.py
-    - python3 demos/sampling.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_tomography:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/tomography.py
-    - python3 demos/tomography.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_wiener_filter_data_space_noiseless:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/wiener_filter_data_space_noiseless.py
-    - python3 demos/wiener_filter_data_space_noiseless.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_wiener_filter_easy.py:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/wiener_filter_easy.py
-    - python3 demos/wiener_filter_easy.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_wiener_filter_via_curvature.py:
-  stage: demo_runs
-  script:
-    - pip install --user numericalunits
-    - pip3 install --user numericalunits
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/wiener_filter_via_curvature.py
-    - python3 demos/wiener_filter_via_curvature.py
-  artifacts:
-    paths:
-      - '*.png'
-
-run_wiener_filter_via_hamiltonian.py:
-  stage: demo_runs
-  script:
-    - python setup.py install --user -f
-    - python3 setup.py install --user -f
-    - python demos/wiener_filter_via_hamiltonian.py
-    - python3 demos/wiener_filter_via_hamiltonian.py
-  artifacts:
-    paths:
-      - '*.png'
-
 run_ipynb:
   stage: demo_runs
   script:
diff --git a/demos/Wiener_Filter.ipynb b/demos/Wiener_Filter.ipynb
index bf80aedf74362b16fb181e82542c6b941318e2b5..038efaffba09a6cf4a8a5e82e44255e832730ca0 100644
--- a/demos/Wiener_Filter.ipynb
+++ b/demos/Wiener_Filter.ipynb
@@ -717,21 +717,21 @@
  "metadata": {
   "celltoolbar": "Slideshow",
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.15"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.5"
   }
  },
  "nbformat": 4,