219697e created the issue

Being a webdevloper I always connect with different hosting servers.

One particular server (without cPanel, but custom managed) which is configured to connect via FTPS (Explicit Auth TLS) was working ok until 7.3.0 update.

Since the update I can:

• connect to the server
• browse files
• delete files

I cannot:

• upload files (it only puts an empty file, 0 kb and raises error 425, Connection failed 425 Unable to build data connection: Operation not permitted.)
• create file (the same as above, empty file and the same error)
• download / edit files (the same error)

Lates version 7.3.1 does the same

All the other servers / connections seem fine.

I've downloaded version 7.2.5 and it works.

With other clients (like latest Transmit) it's also working.

I suspect there might be some sensitive info in the updated TLS or someting.

That particular server is behind a proxypass, maybe this matters.