HTTPS requests fail using HTTP action

[Rogier]

For a while now I've been experiencing problems with HTTPS requests, using the HTTP action in Visual Build Pro 9 (using the latest v9.7 from January 10, 2019).

See a minimal example .bld here:
https://pastebin.com/raw/eiaws20L

This dummy project retrieves http://www.example.com/ through a normal GET request and logs the result. Works fine.

However, now instead I try to retrieve https://www.example.com/ (note the https) by changing the Protocol in the Security tab of the HTTP step into anything but None.

It always fails:

Connecting to HTTPS server 'www.example.com' on port 443
Error connecting to HTTP server: Unable to establish security context for this session

Doesn't matter whether I select TLS 1.2, or TLS, or SSL, or PCT, or "SSL, TLS, or PCT". Also enabling the "Fallback to insecure ciphers" option (where applicable) makes no difference.

I'm using the example.com just as a reference URL, it seems to fail on any HTTPS request.

Am I doing something wrong, or what can be causing this?