Description:
Trying to use an FTPS server, both explicitly and implicitly, fails. LibreOffice should support FTP-over-TLS for security of both credentials and content.

Steps to Reproduce:
1. Set up FTP server that supports TLS (I tested with FileZilla)
2. Start LibO, go to Remote Files
3. Add service pointing to the server, using the implicit TLS port.
4. LibO hangs for a minute, then reports a "general I/O error"
5. Change to explicit TLS port number
6. LibO connects without AUTH TLS, so passing everything in the clear.

Actual Results:
LibO connects without issuing AUTH TLS. Happens on 6.4.6.2 and 7.0.1.2.

Expected Results:
LibO should issue AUTH TLS to use TLS to encrypt credentials and content.


Reproducible: Always


User Profile Reset: Yes



Additional Info:
Version: 6.4.6.2 (x64)
Build ID: 0ce51a4fd21bff07a5c061082cc82c5ed232f115
CPU threads: 4; OS: Windows 10.0 Build 18363; UI render: GL; VCL: win; 
Locale: en-US (en_US); UI-Language: en-US
Calc: threaded