I get an error when opening a villager transaction.

ProtocolLib v5.2.0

[18:51:52 ERROR]: [ItemsAdder] Unhandled exception occurred in onPacketSending(PacketEvent) for ItemsAdder
java.lang.UnsupportedOperationException: com.google.gson.JsonSyntaxException: Expected id to be a string, was an array ([130...95])
at lonelibs.net.kyori.adventure.platform.bukkit.MinecraftComponentSerializer.serialize(MinecraftComponentSerializer.java:257) ~[LoneLibs.jar:?]
at ia.nms.hH.hH.a(SourceFile:101) ~[ItemsAdder_3.6.2c.jar:?]
at ia.m.hy.onPacketSending(SourceFile:172) ~[ItemsAdder_3.6.2c.jar:?]
at com.comphenix.protocol.injector.SortedPacketListenerList.invokeSendingListener(SortedPacketListenerList.java:219) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.SortedPacketListenerList.invokeUnpackedPacketSending(SortedPacketListenerList.java:204) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.SortedPacketListenerList.invokePacketSending(SortedPacketListenerList.java:149) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.SortedPacketListenerList.invokePacketSending(SortedPacketListenerList.java:139) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.PacketFilterManager.postPacketToListeners(PacketFilterManager.java:553) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.PacketFilterManager.invokePacketSending(PacketFilterManager.java:526) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.netty.manager.NetworkManagerInjector.onPacketSending(NetworkManagerInjector.java:100) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.netty.channel.NettyChannelInjector.processOutbound(NettyChannelInjector.java:553) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.netty.channel.NettyChannelInjector$2.doProxyRunnable(NettyChannelInjector.java:456) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.netty.channel.NettyEventLoopProxy.proxyRunnable(NettyEventLoopProxy.java:43) ~[ProtocolLib .jar:?]
at com.comphenix.protocol.injector.netty.channel.NettyEventLoopProxy.execute(NettyEventLoopProxy.java:252) ~[ProtocolLib .jar:?]
at net.minecraft.network.Connection.sendPacket(Connection.java:449) ~[?:?]
at net.minecraft.network.Connection.processQueue(Connection.java:564) ~[?:?]
at net.minecraft.network.Connection.flushQueue(Connection.java:520) ~[?:?]
at net.minecraft.network.Connection.send(Connection.java:411) ~[?:?]
at net.minecraft.server.network.ServerGamePacketListenerImpl.send(ServerGamePacketListenerImpl.java:2217) ~[?:?]
at net.minecraft.server.network.ServerGamePacketListenerImpl.send(ServerGamePacketListenerImpl.java:2203) ~[?:?]
at net.minecraft.server.level.ServerPlayer.openMenu(ServerPlayer.java:1594) ~[?:?]
at net.minecraft.world.item.trading.Merchant.openTradingScreen(Merchant.java:41) ~[?:?]
at net.minecraft.world.entity.npc.Villager.startTrading(Villager.java:351) ~[?:?]
at net.minecraft.world.entity.npc.Villager.mobInteract(Villager.java:329) ~[?:?]
at net.minecraft.world.entity.Mob.interact(Mob.java:1331) ~[?:?]
at net.minecraft.world.entity.player.Player.interactOn(Player.java:1129) ~[?:?]
at net.minecraft.server.network.ServerGamePacketListenerImpl$4.performInteraction(ServerGamePacketListenerImpl.java:2876) ~[?:?]
at net.minecraft.server.network.ServerGamePacketListenerImpl$4.a(ServerGamePacketListenerImpl.java:2896) ~[?:?]
at net.minecraft.network.protocol.game.ServerboundInteractPacket$InteractionAction.dispatch(ServerboundInteractPacket.java:131) ~[?:?]
at net.minecraft.network.protocol.game.ServerboundInteractPacket.dispatch(ServerboundInteractPacket.java:80) ~[?:?]
at net.minecraft.server.network.ServerGamePacketListenerImpl.handleInteract(ServerGamePacketListenerImpl.java:2837) ~[?:?]
at net.minecraft.network.protocol.game.ServerboundInteractPacket.handle(ServerboundInteractPacket.java:67) ~[?:?]
at net.minecraft.network.protocol.game.ServerboundInteractPacket.handle(ServerboundInteractPacket.java:12) ~[?:?]
at net.minecraft.network.protocol.PacketUtils.lambda$ensureRunningOnSameThread$0(PacketUtils.java:51) ~[?:?]
at net.minecraft.server.TickTask.run(TickTask.java:18) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.util.thread.BlockableEventLoop.doRunTask(BlockableEventLoop.java:153) ~[?:?]
at net.minecraft.util.thread.ReentrantBlockableEventLoop.doRunTask(ReentrantBlockableEventLoop.java:24) ~[?:?]
at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:1338) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.server.MinecraftServer.d(MinecraftServer.java:197) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.util.thread.BlockableEventLoop.pollTask(BlockableEventLoop.java:126) ~[?:?]
at net.minecraft.server.MinecraftServer.pollTaskInternal(MinecraftServer.java:1315) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.server.MinecraftServer.pollTask(MinecraftServer.java:1308) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.util.thread.BlockableEventLoop.managedBlock(BlockableEventLoop.java:136) ~[?:?]
at net.minecraft.server.MinecraftServer.waitUntilNextTick(MinecraftServer.java:1286) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1174) ~[paper-1.20.1.jar:git-Paper-196]
at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:317) ~[paper-1.20.1.jar:git-Paper-196]
at java.lang.Thread.run(Thread.java:833) ~[?:?]
Caused by: com.google.gson.JsonSyntaxException: Expected id to be a string, was an array ([130...95])
at net.minecraft.util.GsonHelper.convertToString(GsonHelper.java:94) ~[?:?]
at net.minecraft.util.GsonHelper.getAsString(GsonHelper.java:100) ~[?:?]
at net.minecraft.network.chat.HoverEvent$EntityTooltipInfo.create(HoverEvent.java:177) ~[?:?]
at net.minecraft.network.chat.HoverEvent$Action.deserialize(HoverEvent.java:136) ~[?:?]
at net.minecraft.network.chat.HoverEvent.deserialize(HoverEvent.java:80) ~[?:?]
at net.minecraft.network.chat.Style$Serializer.getHoverEvent(Style.java:405) ~[?:?]
at net.minecraft.network.chat.Style$Serializer.deserialize(Style.java:377) ~[?:?]
at net.minecraft.network.chat.Style$Serializer.deserialize(Style.java:364) ~[?:?]
at com.google.gson.internal.bind.TreeTypeAdapter.read(TreeTypeAdapter.java:76) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1214) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1319) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1290) ~[gson-2.10.jar:?]
at com.google.gson.internal.bind.TreeTypeAdapter$GsonContextImpl.deserialize(TreeTypeAdapter.java:179) ~[gson-2.10.jar:?]
at net.minecraft.network.chat.Component$Serializer.deserialize(Component.java:361) ~[?:?]
at net.minecraft.network.chat.Component$Serializer.deserialize(Component.java:222) ~[?:?]
at com.google.gson.internal.bind.TreeTypeAdapter.read(TreeTypeAdapter.java:76) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1214) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1319) ~[gson-2.10.jar:?]
at com.google.gson.Gson.fromJson(Gson.java:1261) ~[gson-2.10.jar:?]
at net.minecraft.network.chat.Component$Serializer.fromJson(Component.java:536) ~[?:?]
at lonelibs.net.kyori.adventure.platform.bukkit.MinecraftComponentSerializer.serialize(MinecraftComponentSerializer.java:253) ~[LoneLibs.jar:?]
... 46 more
[18:51:52 ERROR]: Parameters:
net.minecraft.network.protocol.game.PacketPlayOutOpenWindow@3bb05996[
a=25
b=net.minecraft.world.inventory.Containers@a3356ec
c=translation{key='entity.minecraft.villager.fisherman', args=[]}[style={hoverEvent=HoverEvent{action=, value='net.minecraft.network.chat.ChatHoverable$b@6e3c9f3'},insertion=4d8c2982-a9a2-478b-9510-c4db1851ff73}]

Please report this to ItemsAdder, due to the plugin being close-source there is no way for us to tell what is going on, and if this even is an issue caused by ProtocolLib. If it really is an issue with ProtocolLib, then the developer of ItemsAdder should open up a bug report, sharing the code he wrote, so that we can reproduce the issue and decide on the next steps to fix the issue :)