Using client certificates leads to ERR_SSL_CLIENT_AUTH_NO_COMMON_ALGORITHMS

I've got a TLS1.2 server that may accept a client certificate. (It works even without one.)

• If the client certificate is added to Windows' OS store (Chrome -> Privacy -> Security -> Manage certificates -> Add the .pfx file there), then QtWebEngine automatically picks it up, and offers it via the QWebEnginePage::selectClientCertificate API. Everything works fine.

• If the client certificate is instead loaded in the app (via QSslCertificate::importPkcs12) and added programmatically to the in-memory store via QWebEngineClientCertificateStore::add , then again it is offered through QWebEnginePage::selectClientCertificate, but then the handshake fails with a ERR_SSL_CLIENT_AUTH_NO_COMMON_ALGORITHMS error.

I'm not really sure what's going on.

The only hit on Google is someone asking about this very problem on SO! https://stackoverflow.com/questions/70680355/minimal-working-example-of-qwebengine-with-client-certificates