diff --git a/src/sonatoki/Preprocessors.py b/src/sonatoki/Preprocessors.py
index 4dc4ab2..4b14dc9 100644
--- a/src/sonatoki/Preprocessors.py
+++ b/src/sonatoki/Preprocessors.py
@@ -150,8 +150,8 @@ class Codeblock(RegexPreprocessor):
     """
 
     pattern = re.compile(
-        r"^```(?:[\w\-]+)?$(?:(?!```).*?)^```$",
-        flags=re.MULTILINE | re.DOTALL,
+        r"```.+?```",
+        flags=re.DOTALL,
     )
 
 
diff --git a/tests/test_preprocessors.py b/tests/test_preprocessors.py
index 63a7702..cb577de 100644
--- a/tests/test_preprocessors.py
+++ b/tests/test_preprocessors.py
@@ -63,6 +63,12 @@ def test_Backticks(s: str):
 second blocky message
 ```"""
 )
+@example(
+    """```oisandm123-_mu
+arbitrary content
+```"""
+)
+@example("""```mu```""")
 def test_Codeblock(s: str):
     res = Codeblock.process(s).strip()
     assert res == "", (repr(s), repr(res))