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You might just have to go back to 1.12.2 until it's updated :(( That's what I had to do
Only problem, I can't. I've tried everything, and either the host for my Minecraft just won't let me downgrade or I'm just really bad at this, but it forces me to update if I want to play it at all and there's no way I can find out (or anyone else I asked) how to go back to the version before.
Have you gone to "Launch Settings" to try and change the configuration or have deleted Minecraft off your computer and redownloaded it? :((
Oh, wow, that worked. I tried pressing the 'Launch Options' and stuff but I never noticed any difference until now. You are truly goddess *praise*
omg yay I'm so glad it worked!!!! :DDD