/usr/include/thunderbird/google/ is in thunderbird-dev 1:38.6.0+build1-0ubuntu1.
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/usr/include/thunderbird/google/protobuf/
/usr/include/thunderbird/google/protobuf/extension_set.h
/usr/include/thunderbird/google/protobuf/generated_message_util.h
/usr/include/thunderbird/google/protobuf/io/
/usr/include/thunderbird/google/protobuf/io/coded_stream.h
/usr/include/thunderbird/google/protobuf/io/coded_stream_inl.h
/usr/include/thunderbird/google/protobuf/io/package_info.h
/usr/include/thunderbird/google/protobuf/io/zero_copy_stream.h
/usr/include/thunderbird/google/protobuf/io/zero_copy_stream_impl.h
/usr/include/thunderbird/google/protobuf/io/zero_copy_stream_impl_lite.h
/usr/include/thunderbird/google/protobuf/message_lite.h
/usr/include/thunderbird/google/protobuf/repeated_field.h
/usr/include/thunderbird/google/protobuf/stubs/
/usr/include/thunderbird/google/protobuf/stubs/common.h
/usr/include/thunderbird/google/protobuf/stubs/hash.h
/usr/include/thunderbird/google/protobuf/stubs/map-util.h
/usr/include/thunderbird/google/protobuf/stubs/once.h
/usr/include/thunderbird/google/protobuf/stubs/stl_util-inl.h
/usr/include/thunderbird/google/protobuf/wire_format_lite.h
/usr/include/thunderbird/google/protobuf/wire_format_lite_inl.h