(Mirrored from my entry on the Discord forum thread: "Fabric 1.20.1 instant crash")

The client crashes on launch with the following error:

[26May2024 10:42:30.882] [main/ERROR] [mixin/]: Error loading companion plugin class [dev.tonimatas.packetfixer.mixins.MixinConfigPlugin] for mixin config [packetfixer-common.mixins.json]. The plugin may be out of date: UnsupportedClassVersionError:dev/tonimatas/packetfixer/mixins/MixinConfigPlugin has been compiled by a more recent version of the Java Runtime (class file version 65.0), this version of the Java Runtime only recognizes class file versions up to 61.0
java.lang.UnsupportedClassVersionError: dev/tonimatas/packetfixer/mixins/MixinConfigPlugin has been compiled by a more recent version of the Java Runtime (class file version 65.0), this version of the Java Runtime only recognizes class file versions up to 61.0

This was tested on a clean 1.20.1 NeoForge install with no other mods installed. Logfile.
I am running JRE 8u411 (latest).

(Mirrored from my entry on the Discord forum thread: "Fabric 1.20.1 instant crash")

The client crashes on launch with the following error:

[26May2024 10:42:30.882] [main/ERROR] [mixin/]: Error loading companion plugin class [dev.tonimatas.packetfixer.mixins.MixinConfigPlugin] for mixin config [packetfixer-common.mixins.json]. The plugin may be out of date: UnsupportedClassVersionError:dev/tonimatas/packetfixer/mixins/MixinConfigPlugin has been compiled by a more recent version of the Java Runtime (class file version 65.0), this version of the Java Runtime only recognizes class file versions up to 61.0
java.lang.UnsupportedClassVersionError: dev/tonimatas/packetfixer/mixins/MixinConfigPlugin has been compiled by a more recent version of the Java Runtime (class file version 65.0), this version of the Java Runtime only recognizes class file versions up to 61.0

This was tested on a clean 1.20.1 NeoForge install with no other mods installed. Logfile. I am running JRE 8u411 (latest).

Redownload it