C++ header in a C++ project parsed as C

See image.

The hints coming from the code model are clearly about C, like
"unknown type name 'template'"
"must use enum tag to refer to type "class'"

The screenshot clearly shows this file is part of the QmlModels project, which is CXX17.

master @ a69ff75357d98258502dc1b802d4d066d8b426b0
LLVM 15.0.7