don't add new parameter

CHANGELOG.md

@@ -11,7 +11,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 
 - Added Styles.has_any_rules https://github.com/Textualize/textual/pull/5264
-- Added `active_effect_duration` to `Button.__init__` https://github.com/Textualize/textual/pull/5267
 
 ### Fixed 
 

src/textual/widgets/_button.py

@@ -204,7 +204,6 @@ class Button(Widget, can_focus=True):
             disabled: Whether the button is disabled or not.
             tooltip: Optional tooltip.
             action: Optional action to run when clicked.
-            active_effect_duration: Amount of time in seconds the button 'press' animation lasts.
         """
         super().__init__(name=name, id=id, classes=classes, disabled=disabled)
 
@@ -214,7 +213,7 @@ class Button(Widget, can_focus=True):
         self.label = label
         self.variant = variant
         self.action = action
-        self.active_effect_duration = active_effect_duration
+        self.active_effect_duration = 0.2
         """Amount of time in seconds the button 'press' animation lasts."""
 
         if tooltip is not None:

tests/test_widget.py

@@ -452,7 +452,7 @@ async def test_loading_button():
 
     class LoadingApp(App):
         def compose(self) -> ComposeResult:
-            yield Button("Hello, World", action="app.inc", active_effect_duration=0)
+            yield Button("Hello, World", action="app.inc")
 
         def action_inc(self) -> None:
             nonlocal counter
@@ -462,16 +462,18 @@ async def test_loading_button():
         # Sanity check
         assert counter == 0
 
+        button = pilot.app.query_one(Button)
+        button.active_effect_duration = 0
+
         # Click the button to advance the counter
-        await pilot.click(Button)
+        await pilot.click(button)
         assert counter == 1
 
         # Set the button to loading state
-        button = pilot.app.query_one(Button)
         button.loading = True
 
         # A click should do nothing
-        await pilot.click(Button)
+        await pilot.click(button)
         assert counter == 1
 
         # Set the button to not loading