diff --git a/.github/workflows/pytest_and_coverage.yml b/.github/workflows/pytest_and_coverage.yml
index d125d31..e6416ce 100644
--- a/.github/workflows/pytest_and_coverage.yml
+++ b/.github/workflows/pytest_and_coverage.yml
@@ -11,6 +11,7 @@ jobs:
         python-version: [3.8, 3.9, '3.10', '3.11']
     runs-on: ${{ matrix.runs-on }}
     env:
+        MPLBACKEND: Agg
         USE_COVERAGE: ${{ matrix.runs-on == 'ubuntu-latest' && matrix.python-version == '3.10' }}
 
     steps: