and should be fixed when we switch to newer Espressif SDK : https://github.com/esp8266/Arduino/issues/1926
Any idea of when the switch to the newer Espressif SDK will occur? Also once this happens will an updated library be posted for the arduino IDE or is there some specific site / URL I should watch for the update to appear on so I can pull the new library?
Lastly, I know you said this was introduced with this rev of the library, but does a previous rev exist where the multicast function worked, or has it always been broken?
(upgrade/reinstall will be done using BoardManager, otherwise manual copying files is a bit tedious, although doable)
For previous version, I don't know since I'm not using UDP, but according to the fact that the flood of those stacktrace came recently, I presume that probably the 2.1.0 didn't have the issue.