Package: khtml Version: 5.28.0-1 Severity: serious khtml B-D on libssl-dev and has been built against it in the archive. I am not entirely sure that this works. I doubt because QT itself uses libssl1.0.2 and passing around SSL, SSL_CTX, BIO or any other struct is a no no. Additionally some of the symbols, that khtml loads via dlopen(), are no longer exported by libssl1.1. Therefore I think it is best to change the B-D to libssl1.0-dev | libssl-dev (<< 1.1) for Stretch.
Sebastian