diff --git a/setup.py b/setup.py
index 30f8625c8..91b3e12cc 100644
--- a/setup.py
+++ b/setup.py
@@ -38,6 +38,9 @@ extras_require = {
     ':sys_platform=="win32"': [
         'colorama>=0.3.5',
     ],
+    'docs': [
+        'sphinxcontrib-websupport',
+    ],
     'test': [
         'pytest',
         'pytest-cov',
diff --git a/tox.ini b/tox.ini
index ea404b4a8..64bebf2fb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -15,7 +15,6 @@ deps =
     du14: docutils==0.14
 extras =
     test
-    websupport
 setenv =
     PYTHONWARNINGS = all,ignore::ImportWarning:pkgutil,ignore::ImportWarning:importlib._bootstrap,ignore::ImportWarning:importlib._bootstrap_external,ignore::ImportWarning:pytest_cov.plugin,ignore::DeprecationWarning:site,ignore::DeprecationWarning:_pytest.assertion.rewrite,ignore::DeprecationWarning:_pytest.fixtures,ignore::DeprecationWarning:distutils
 commands=
@@ -62,8 +61,8 @@ commands=
 basepython = python3
 description =
     Build documentation.
-deps =
-    sphinxcontrib-websupport
+extras =
+    docs
 commands =
     python setup.py build_sphinx {posargs}