VS Code debugger shows String variables as "Summary Unavailable"

I am trying to debug the very simple helloworld.cpp example in VS Code with the C++ extension on macOS X. However, string variables in the debugger don't print correctly where the length of the string is less than 22 bytes,. Instead of showing, for example, "Hello", the debugger shows Summary Unavailable.

VS Code debugger local variables:

(To be clear, for any for whom the image is not visible, the debugger front end shows "Summary Unavailable" as the value of local variables such as word instead of the expected value of the variable, if the strength length is shorter than 22bytes, apparently the limit for short string optimisation on OS X per this answer.)

My tasks.json is set up to build using C++17, and the launch.json is the standard generated by VS Code.

The code being debugged is based on the standard VS Code C++ example used in the VS Code introduction:

#include <iostream>
#include <vector>
#include <string>

using namespace std;

int main()
{
    vector<string> msg {"Hello", "C++", "World", "from", "VS Code", "and also from the C++ extension!"};
    
    for (const string& word : msg)
    {
        cout << word << " ";
    }
    cout << endl;
}

I've tried running this with both the CLT and Xcode.app installed, but I get the same result.