diff --git .clang-format .clang-format
index 87ff0884ee821..5a40766bbe63e 100644
--- .clang-format
+++ .clang-format
@@ -12,43 +12,6 @@ Standard: Cpp11
 InsertBraces: true
 InsertNewlineAtEOF: true
 
-# Sort #includes by following
-# https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes
-#
-# ref: https://clang.llvm.org/docs/ClangFormatStyleOptions.html#includeblocks
-IncludeBlocks: Regroup
-# ref: https://clang.llvm.org/docs/ClangFormatStyleOptions.html#includecategories
-IncludeCategories:
-  # The win32 api has all sorts of implicit include order dependencies :-/
-  # Give a few headers special priorities that make sure they appear before
-  # all other headers.
-  # Sync this with SerializeIncludes in tools/add_header.py.
-  # TODO(crbug.com/329138753): remove include sorting from tools/add_header.py
-  # after confirming clang-format sort works well.
-  # LINT.IfChange(winheader)
-  - Regex:           '^<objbase\.h>' # This has to be before initguid.h.
-    Priority:        1
-  - Regex:           '^<(initguid|mmdeviceapi|windows|winsock2|ws2tcpip|shobjidl|atlbase|ole2|unknwn|tchar)\.h>'
-    Priority:        2
-  # LINT.ThenChange(/tools/add_header.py:winheader)
-  # UIAutomation*.h need to be after base/win/atl.h.
-  # Note the low priority number.
-  - Regex:           '^<UIAutomation.*\.h>'
-    Priority:        6
-  # Other C system headers.
-  - Regex:           '^<.*\.h>'
-    Priority:        3
-  # C++ standard library headers.
-  - Regex:           '^<.*'
-    Priority:        4
-  # Other libraries.
-  - Regex:           '.*'
-    Priority:        5
-# ref: https://clang.llvm.org/docs/ClangFormatStyleOptions.html#includeismainregex
-IncludeIsMainRegex: "\
-(_(32|64|android|apple|chromeos|freebsd|fuchsia|fuzzer|ios|linux|mac|nacl|openbsd|posix|stubs?|win))?\
-(_(unit|browser|perf)?tests?)?$"
-
 # Make sure code like:
 # IPC_BEGIN_MESSAGE_MAP()
 #   IPC_MESSAGE_HANDLER(WidgetHostViewHost_Update, OnUpdate)