diff --git a/.travis.yml b/.travis.yml
index 79afe10..be759da 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -40,6 +40,8 @@ jobs:
       env: TOXENV=py36-pytestlatest
     - python: "3.7"
       env: TOXENV=py37-pytestlatest
+    - python: "3.9-dev"
+      env: TOXENV=py39-pytestlatest
     - python: "3.8"
       env: TOXENV=py38-pytestmaster
 
diff --git a/testing/acceptance_test.py b/testing/acceptance_test.py
index 77e8ce4..5b19ee6 100644
--- a/testing/acceptance_test.py
+++ b/testing/acceptance_test.py
@@ -1,6 +1,5 @@
 import os
 import re
-import sys
 import textwrap
 
 import py
@@ -577,16 +576,8 @@ def test_fixture_teardown_failure(testdir):
     assert result.ret
 
 
-@pytest.mark.skipif(
-    sys.version_info[:2] == (2, 7),
-    reason="Only available in pytest 5.0+ (Python 3 only)",
-)
 def test_config_initialization(testdir, monkeypatch, pytestconfig):
     """Ensure workers and master are initialized consistently. Integration test for #445"""
-    if not hasattr(pytestconfig, "invocation_params"):
-        pytest.skip(
-            "requires pytest >=5.1 (config has no attribute 'invocation_params')"
-        )
     testdir.makepyfile(
         **{
             "dir_a/test_foo.py": """
diff --git a/tox.ini b/tox.ini
index 584d3ed..d532a2f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,7 @@
 [tox]
 envlist=
   linting
-  py{35,36,37,38}-pytestlatest
+  py{35,36,37,38,39}-pytestlatest
   py38-pytestmaster
 
 [testenv]