trev,
Thanks for your reply and advice!
I will wait for the official release of Lazarus with this improvement.
However I'm a bit concerned about OpenSSL support in future macOS versions.
On other hand, ns_url_request by Phil Hess also doesn't show a stable work, when I tested it on Catalina it hangs with timeout every 3-5 run. I have no idea why it happens. Even a simple GET request may hung with timeout exit.