diff --git a/isort/core.py b/isort/core.py
index 663dd669..37c8fc31 100644
--- a/isort/core.py
+++ b/isort/core.py
@@ -516,7 +516,7 @@ def _indented_config(config: Config, indent: str) -> Config:
 def _has_changed(before: str, after: str, line_separator: str, ignore_whitespace: bool) -> bool:
     if ignore_whitespace:
         return (
-            remove_whitespace(before, line_separator=line_separator).strip()
-            != remove_whitespace(after, line_separator=line_separator).strip()
+            remove_whitespace(before, line_separator=line_separator).rstrip()
+            != remove_whitespace(after, line_separator=line_separator).rstrip()
         )
-    return before.strip() != after.strip()
+    return before.rstrip() != after.rstrip()