io.netty.ChannelException: failed to open a new selector

when I enter minecraft and try to go to a multiserver it never loads and it wont let me go into my world either.?

*What I expected to happen was...:
I thought i would just go into minecraft and it would work

What actually happened was...:
I went into minecraft and then I went to multiplayer and clicked on a server and then it just wouldnt let me go in it i refreshed refreshed and refreshed and nothing and then i tried going into my world and then it crashed and thats how i got here

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
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