diff --git a/manim/mobject/geometry/line.py b/manim/mobject/geometry/line.py
index be6c3a77ba..8c3fb5c3ef 100644
--- a/manim/mobject/geometry/line.py
+++ b/manim/mobject/geometry/line.py
@@ -133,7 +133,7 @@ def _account_for_buff(self, buff: float) -> None:
         if length < 2 * buff:
             return
         buff_proportion = buff / length
-        self.pointwise_become_partial(self, buff_proportion, 1 - buff_proportion)
+        self.pointwise_become_partial(self.copy(), buff_proportion, 1 - buff_proportion)
         return
 
     def _set_start_and_end_attrs(