diff --git a/.github/workflows/ci_workflows.yml b/.github/workflows/ci_workflows.yml
index a968a0c..5ed76b0 100644
--- a/.github/workflows/ci_workflows.yml
+++ b/.github/workflows/ci_workflows.yml
@@ -60,7 +60,7 @@ jobs:
           # Windows - just the oldest, stable, and dev
           - os: windows-latest
             python-version: 3.8
-            toxenv: py38-test-sphinx40
+            toxenv: py38-test-sphinx_oldest
           - os: windows-latest
             python-version: '3.10'
             toxenv: py310-test-sphinx72
diff --git a/.readthedocs.yml b/.readthedocs.yml
index 93f9723..c85d6b6 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -18,7 +18,6 @@ sphinx:
   fail_on_warning: true
 
 python:
-  system_packages: false
   install:
     - method: pip
       path: .