--- a/mercurial/filemerge.py	Mon Jan 18 22:32:09 2021 -0800
+++ b/mercurial/filemerge.py	Tue Jan 19 14:00:42 2021 -0800
@@ -1195,7 +1195,11 @@
 
 def hasconflictmarkers(data):
     return bool(
-        re.search(b"^(<<<<<<< .*|=======|>>>>>>> .*)$", data, re.MULTILINE)
+        re.search(
+            br"^(<<<<<<<.*|=======.*|------- .*|\+\+\+\+\+\+\+ .*|>>>>>>>.*)$",
+            data,
+            re.MULTILINE,
+        )
     )