diff --git a/.github/workflows/gh-ci.yaml b/.github/workflows/gh-ci.yaml
index 6dd14a6..46f341c 100644
--- a/.github/workflows/gh-ci.yaml
+++ b/.github/workflows/gh-ci.yaml
@@ -26,7 +26,13 @@ jobs:
         python-version: [2.7, 3.5, 3.6, 3.7, 3.8, 3.9]
         include:
           - os: windows-latest
-            python-version: 3.7
+            python-version: 2.7	
+          - os: windows-latest
+            python-version: 3.9
+          - os: macos-latest
+            python-version: 2.7	    
+          - os: macos-latest
+            python-version: 3.9
 
     steps:
     - uses: actions/checkout@v2
@@ -58,7 +64,7 @@ jobs:
 
     - name: run unit tests
       run: |
-        pytest -v --cov=gridData --cov-report=xml ./gridData/tests
+        pytest -v --cov=gridData --cov-report=xml --color=yes ./gridData/tests
 
     - name: codecov
       uses: codecov/codecov-action@v2
diff --git a/CHANGELOG b/CHANGELOG
index 7fc696c..e3a7805 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -13,15 +13,20 @@ The rules for this file:
   * accompany each entry with github issue/PR number (Issue #xyz)
 
 ------------------------------------------------------------------------------
-??/??/2019 eloyfelix, renehamburger1993, lilyminium, jvermaas
+10/10/2021 eloyfelix, renehamburger1993, lilyminium, jvermaas, xiki-tempula,
+           IAlibay, orbeckst
 
   * 0.6.0
 
+  Changes
+  * macOS and Windows are also tested (min and max supported Python, #97)
+  * switched CI to using GitHub actions (#86)
+
   Enhancements
 
-  * Allow parsing/writing gzipped DX files
+  * Allow parsing/writing gzipped DX files (PR #70, #99)
   * Update doc theme to use sphinx-rtd-theme (#80)
-  * Delta of OpenDX writes 7 significant figures (#89)
+  * Delta of OpenDX writes 7 significant figures (#88)
 
   Fixes
 
diff --git a/gridData/OpenDX.py b/gridData/OpenDX.py
index 3099e1f..97d6174 100644
--- a/gridData/OpenDX.py
+++ b/gridData/OpenDX.py
@@ -174,6 +174,17 @@
 
 import warnings
 
+# Python 2/3 compatibility (see issue #99)
+# and https://bugs.python.org/issue30012
+import sys
+if sys.version_info >= (3, ):
+    def _gzip_open(filename, mode="rt"):
+        return gzip.open(filename, mode)
+else:
+    def _gzip_open(filename, mode="rt"):
+        return gzip.open(filename)
+del sys
+
 class DXclass(object):
     """'class' object as defined by OpenDX"""
     def __init__(self,classid):
@@ -707,7 +718,7 @@ def parse(self, DXfield):
         self.tokens = []                    # token buffer
 
         if self.filename.endswith('.gz'):
-            with gzip.open(self.filename, 'rt') as self.dxfile:
+            with _gzip_open(self.filename, 'rt') as self.dxfile:
                 self.use_parser('general')
         else:
             with open(self.filename, 'r') as self.dxfile:
diff --git a/setup.py b/setup.py
index 6d5f518..b12b739 100644
--- a/setup.py
+++ b/setup.py
@@ -14,6 +14,7 @@
       cmdclass=versioneer.get_cmdclass(),
       description="Reading and writing of data on regular grids in Python",
       long_description=long_description,
+      long_description_content_type="text/x-rst",
       author="Oliver Beckstein",
       author_email="orbeckst@gmail.com",
       license="LGPLv3",