More complicated patch
https://github.com/Kamilcuk/clickdc/pull/3

--- a/tests/test.py
+++ b/tests/test.py
@@ -11,7 +11,7 @@ import clickdc
 
 
 def invoke(*args, **kwargs):
-    return CliRunner(mix_stderr=True).invoke(*args, **kwargs)
+    return CliRunner().invoke(*args, **kwargs)
 
 
 def run(arg_class, input: str, output: Any = None, fail: int = 0, toargs: bool = False):