diff --git a/scrapy/addons.py b/scrapy/addons.py
index f1ddfd211..02dd4fde8 100644
--- a/scrapy/addons.py
+++ b/scrapy/addons.py
@@ -40,12 +40,9 @@ class AddonManager:
                 self.addons.append(addon)
             except NotConfigured as e:
                 if e.args:
-                    clsname = (
-                        clspath.split(".")[-1] if isinstance(clspath, str) else clspath
-                    )
                     logger.warning(
-                        "Disabled %(clsname)s: %(eargs)s",
-                        {"clsname": clsname, "eargs": e.args[0]},
+                        "Disabled %(clspath)s: %(eargs)s",
+                        {"clspath": clspath, "eargs": e.args[0]},
                         extra={"crawler": self.crawler},
                     )
         logger.info(
diff --git a/scrapy/middleware.py b/scrapy/middleware.py
index 03e92b565..04b838d2d 100644
--- a/scrapy/middleware.py
+++ b/scrapy/middleware.py
@@ -46,10 +46,9 @@ class MiddlewareManager:
                 enabled.append(clspath)
             except NotConfigured as e:
                 if e.args:
-                    clsname = clspath.split(".")[-1]
                     logger.warning(
-                        "Disabled %(clsname)s: %(eargs)s",
-                        {"clsname": clsname, "eargs": e.args[0]},
+                        "Disabled %(clspath)s: %(eargs)s",
+                        {"clspath": clspath, "eargs": e.args[0]},
                         extra={"crawler": crawler},
                     )
 
diff --git a/tests/test_middleware.py b/tests/test_middleware.py
index 00ff746ee..a42c7b3d1 100644
--- a/tests/test_middleware.py
+++ b/tests/test_middleware.py
@@ -39,7 +39,7 @@ class MOff:
         pass
 
     def __init__(self):
-        raise NotConfigured
+        raise NotConfigured("foo")
 
 
 class TestMiddlewareManager(MiddlewareManager):