diff --git a/.travis.yml b/.travis.yml
index 21a356bf..e76e4cab 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -234,7 +234,7 @@ matrix:
               stack exec -- ihaskell install --stack
               test/acceptance.nbconvert.sh stack exec -- jupyter nbconvert
           fi
-    - env: DISPLAY=false   USE_STACK_YAML="stack.yaml"     # GHC 8.6.5
+    - env: DISPLAY=true   USE_STACK_YAML="stack.yaml"     # GHC 8.6.5
       language: python
       dist: xenial
       # Test against different stack LTS versions.
diff --git a/test/acceptance.nbconvert.sh b/test/acceptance.nbconvert.sh
index da261c4d..0732cbd8 100755
--- a/test/acceptance.nbconvert.sh
+++ b/test/acceptance.nbconvert.sh
@@ -29,5 +29,5 @@ set -euo pipefail
 
 $* --to=notebook --execute --allow-errors --stdout test/acceptance.nbconvert.in.ipynb > test/acceptance.nbconvert.out.ipynb
 
-diff <(grep -v 'version' test/acceptance.nbconvert.in.ipynb) <(grep -v 'version' test/acceptance.nbconvert.out.ipynb)
+diff <(grep -v -e 'version' -e 'Line ' test/acceptance.nbconvert.in.ipynb) <(grep -v -e 'version' -e 'Line ' test/acceptance.nbconvert.out.ipynb)