Using latest 1.18.1 version of Connectivity, i am shown this in my latest.log on start
[01Jan2022 08:16:36.185] [main/ERROR] [mixin/]: The specified mixin 'com.connectivity.mixin.ConnectionMixin' was not found
org.spongepowered.asm.mixin.transformer.throwables.InvalidMixinException: The specified mixin 'com.connectivity.mixin.ConnectionMixin' was not found
at org.spongepowered.asm.mixin.transformer.MixinInfo.<init>(MixinInfo.java:864) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinConfig.prepareMixins(MixinConfig.java:850) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinConfig.prepare(MixinConfig.java:775) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinProcessor.prepareConfigs(MixinProcessor.java:539) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinProcessor.select(MixinProcessor.java:462) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinProcessor.checkSelect(MixinProcessor.java:438) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:290) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClass(MixinTransformer.java:250) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.service.modlauncher.MixinTransformationHandler.processClass(MixinTransformationHandler.java:131) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.launch.MixinLaunchPluginLegacy.processClass(MixinLaunchPluginLegacy.java:131) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at cpw.mods.modlauncher.serviceapi.ILaunchPluginService.processClassWithFlags(ILaunchPluginService.java:156) ~[modlauncher-9.0.7.jar:9.0.7+91+master.8569cdf]
at cpw.mods.modlauncher.LaunchPluginHandler.offerClassNodeToPlugins(LaunchPluginHandler.java:88) ~[modlauncher-9.0.7.jar:?]
at cpw.mods.modlauncher.ClassTransformer.transform(ClassTransformer.java:120) ~[modlauncher-9.0.7.jar:?]
at cpw.mods.modlauncher.TransformingClassLoader.maybeTransformClassBytes(TransformingClassLoader.java:50) ~[modlauncher-9.0.7.jar:?]
at cpw.mods.cl.ModuleClassLoader.readerToClass(ModuleClassLoader.java:110) ~[securejarhandler-0.9.54.jar:?]
at cpw.mods.cl.ModuleClassLoader.lambda$findClass$16(ModuleClassLoader.java:213) ~[securejarhandler-0.9.54.jar:?]
at cpw.mods.cl.ModuleClassLoader.loadFromModule(ModuleClassLoader.java:223) ~[securejarhandler-0.9.54.jar:?]
at cpw.mods.cl.ModuleClassLoader.findClass(ModuleClassLoader.java:213) ~[securejarhandler-0.9.54.jar:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:632) ~[?:?]
at java.lang.Class.forName(Class.java:545) ~[?:?]
at net.minecraftforge.fml.loading.targets.CommonClientLaunchHandler.lambda$launchService$0(CommonClientLaunchHandler.java:45) ~[fmlloader-1.18.1-39.0.9.jar%2323!:?]
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:53) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:71) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.Launcher.run(Launcher.java:106) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.Launcher.main(Launcher.java:77) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:26) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:23) [modlauncher-9.0.7.jar%235!:?]
at cpw.mods.bootstraplauncher.BootstrapLauncher.main(BootstrapLauncher.java:90) [bootstraplauncher-0.1.17.jar:?]
Caused by: java.lang.ClassNotFoundException: The specified mixin 'com.connectivity.mixin.ConnectionMixin' was not found
at org.spongepowered.asm.mixin.transformer.MixinInfo.loadMixinClass(MixinInfo.java:1313) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
at org.spongepowered.asm.mixin.transformer.MixinInfo.<init>(MixinInfo.java:857) ~[mixin-0.8.5.jar:0.8.5+Jenkins-b310.git-155314e6e91465dad727e621a569906a410cd6f4]
... 28 more
Using latest 1.18.1 version of Connectivity, i am shown this in my latest.log on start