ClientWebSocket connectAsync freezes on 3rd try

Hi,

I am currently working on a WebSocket Library that uses the Experimental .Net 4.6 . When I try to connect multiple times to a server that does not exist I get an Exception for the first 2 tries (which is fine so far) but the ConnectAsync freezes on the 3rd try.
See this gist for example code. The output for this code is this:

HTML:

1. try to connect
Connection Error
2. try to connect
Connection Error
3. try to connect

The 3rd "Connection Error" is never shown/the task is frozen.
Any idea how I can solve this? Ideally it would try to connect to the server forever (I could add some delay that increases over time, but in theory I'd like to have a loop until my server becomes available).

 

I tested a bit more and it looks like it is always the 3rd unsuccessful connection attempt, things like successfully connecting on the 2nd attempt then disconnect and reconnect works. Only 3 unsuccessful connection attempts in a row result in the freeze.

I assume this might be a .Net-Framework issue, so I also chatted with the microsoft support and created an issue on the MS feeback hub as well as the communty forum.

 

Came across this bug as well (spent 2 days trying to figure out why). Seems to be fixed in Unity 2018.