IntelliSense errors with Parsing the .pb.h header file generated from the protobuffer proto file

Environment

• OS and Version: CentOS7
• VS Code Version: 1.98.2
• C/C++ Extension Version: 1.29.3

Bug Summary and Steps to Reproduce

Bug Summary:
Opening the .pb.h header file generated from the .proto file of Protobuf, there is IntelliSense error: this declaration has no storage class or type specifier.

1. My protobuf version is 3.6.0
2. The minimal case might look like this：

#include <google/protobuf/port_def.inc>
#include <google/protobuf/port_undef.inc>
#include <google/protobuf/port_def.inc>
PROTOBUF_NAMESPACE_OPEN
namespace internal {
class AnyMetadata;
}  // namespace internal
PROTOBUF_NAMESPACE_CLOSE

3. Error displayed on macro PROTOBUF_NAMESPACE_OPEN

4. The attachment here is the header file provided by protobuf
   protobuf-include.zip

Configuration and Logs

{
    "configurations": [
        {
            "name": "Linux",
            ],
            "defines": [
                "_DEBUG",
                "UNICODE",
                "_UNICODE"
            ],
            "cStandard": "c11",
            "cppStandard": "c++11",
            "intelliSenseMode": "linux-gcc-x64"
        }
    ],
    "version": 4
}

Other Extensions

No response

Additional context

No response

Start with the minimal .pb.h snippet and the diagnostic on PROTOBUF_NAMESPACE_OPEN, using the reported cStandard, cppStandard, and intelliSenseMode settings. Reproduce with protobuf-include.zip and the listed VS Code and C/C++ extension versions; done means the generated header no longer shows this IntelliSense error.