diff --git a/pyproject.toml b/pyproject.toml
index 798006d22..9006d32fa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -57,7 +57,7 @@ keywords = "raiden, raiden-network"
 [tool.flit.metadata.requires-extra]
 # Extended dependencies required for development and testing. Flit installs
 # these automatically.
-test = ["pytest", "tox"]
+test = ["pytest==4.5.0", "tox"]
 dev = [
     "black==19.3b0",
     "flake8-bugbear==18.8.0",
diff --git a/scenario_player/main.py b/scenario_player/main.py
index bfa9c1373..5e3781e77 100644
--- a/scenario_player/main.py
+++ b/scenario_player/main.py
@@ -29,7 +29,7 @@
 from scenario_player.runner import ScenarioRunner
 from scenario_player.services.common.app import ServiceProcess
 from scenario_player.tasks.base import collect_tasks
-from scenario_player.ui import ScenarioUI, enable_gui_formatting
+from scenario_player.ui import ScenarioUI, attach_urwid_logbuffer
 from scenario_player.utils import (
     ChainConfigType,
     DummyStream,
@@ -153,7 +153,7 @@ def run(
 
     # If the output is a terminal, beautify our output.
     if enable_ui:
-        enable_gui_formatting()
+        log_buffer = attach_urwid_logbuffer()
 
     # Dynamically import valid Task classes from sceanrio_player.tasks package.
     collect_tasks(tasks)
diff --git a/scenario_player/ui.py b/scenario_player/ui.py
index f81025e61..64942316b 100644
--- a/scenario_player/ui.py
+++ b/scenario_player/ui.py
@@ -285,7 +285,7 @@ def set_success(self, success):
             self._loop.screen.register_palette_entry("focus", "dark red", "default")
 
 
-def enable_gui_formatting():
+def attach_urwid_logbuffer():
     """Enable formatted text output for the console UI."""
     log_buffer = UrwidLogWalker([])
     for handler in logging.getLogger("").handlers:
@@ -296,3 +296,4 @@ def enable_gui_formatting():
             )
             handler.stream = log_buffer
             break
+    return log_buffer