To bypass censorship in a DIY fashion, I plan to set up private proxies for my personal use. One of the possible methods I would try is to use an HTTPS proxy (not a web proxy, to be explicit) hosted on an overseas server which is not censored by my ISP.
However, what I have read on the differences between an HTTP and an HTTPS proxy did not provide enough information to clear my concerns over the encryption of traffic between the proxy client and the proxy server. This is critical to a successful mitigation of the censorship by [c_____ed].
According to this diagram, fetching an HTTP URI over an HTTPS proxy has NO difference with doing so over an ordinary HTTP one, except that an SSL/TLS handshake is performed before the HTTP GET request which is unencrypted. If this is the case, communication with the proxy would almost certainly be reset because URL filtering and DPI have long been implemented in my place. The use of HTTPS proxies, then, would be highly limited: if an HTTP-transferred site has a "Share to ..." button containing URL pointing to, let's say Youtube or Facebook, this can be detected and communication to the proxy server is then disrupted.
In addition, I have seen that in the proxy settings page of the mainstream browsers, users are given the option to specify different proxies for HTTP and HTTPS, so does this imply that HTTP requests over HTTP and/or HTTPS proxies can never be encrypted, at least in defined, conventional ways?
I will only set out building an HTTPS proxy provided that all traffic between the proxy client and the proxy server, regardless of it being HTTP or HTTPS, is definitely encrypted, only except for the initiating TCP connections and handshakes.
I look forward to clarification on this issue.