Here's my port 119 (non-TLS, no login, paganini server) results using the comment 63 try build. Unlike what you see from your location, after the server timeout of 30m, the FIN is sent by the server and not by TB.
Bug 1901338 Comment 67 Edit History
Note: The actual edited comment in the bug view page will always show the original commenter’s name and original timestamp.
Here's my port 119 (non-TLS, no login, paganini server) results using the comment 63 try build. ~~Unlike what you see from your location, after the server timeout of 30m, the FIN is sent by the server and not by TB.~~ Edit: Actually, I'm seeing the same thing as David C. here -- see comment 69.