NullPointerException: GameProfile's username cannot be null in newer Minecraft versions

[CdeJong]

It happens when a GameProfile is made to set a skull's owner/texture, but the username is unknown (null).

Issue was reported in the discord, after removing the usercache I did get the same result:

[00:59:29] [Server thread/ERROR]: Error occurred while enabling PWarp v3.0.4 (Is it up to date?)
java.lang.NullPointerException: Profile name must not be null
	at java.util.Objects.requireNonNull(Objects.java:259) ~[?:?]
	at com.mojang.authlib.GameProfile.<init>(GameProfile.java:31) ~[authlib-6.0.52.jar:?]
	at org.bukkit.craftbukkit.v1_20_R3.inventory.CraftMetaSkull.setOwningPlayer(CraftMetaSkull.java:246) ~[paper-1.20.4.jar:git-Paper-409]
	at me.tks.playerwarp.Warp.fromJson(Warp.java:785) ~[PWarp(7).jar:?]
	at me.tks.playerwarp.WarpList.fromJson(WarpList.java:286) ~[PWarp(7).jar:?]
	at me.tks.playerwarp.WarpList.read(WarpList.java:80) ~[PWarp(7).jar:?]
	at me.tks.playerwarp.PWarp.onEnable(PWarp.java:47) ~[PWarp(7).jar:?]
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:281) ~[paper-api-1.20.4-R0.1-SNAPSHOT.jar:?]
	at io.papermc.paper.plugin.manager.PaperPluginInstanceManager.enablePlugin(PaperPluginInstanceManager.java:188) ~[paper-1.20.4.jar:git-Paper-409]
	at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.enablePlugin(PaperPluginManagerImpl.java:104) ~[paper-1.20.4.jar:git-Paper-409]
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:507) ~[paper-api-1.20.4-R0.1-SNAPSHOT.jar:?]
	at org.bukkit.craftbukkit.v1_20_R3.CraftServer.enablePlugin(CraftServer.java:637) ~[paper-1.20.4.jar:git-Paper-409]
	at org.bukkit.craftbukkit.v1_20_R3.CraftServer.enablePlugins(CraftServer.java:548) ~[paper-1.20.4.jar:git-Paper-409]
	at net.minecraft.server.MinecraftServer.loadWorld0(MinecraftServer.java:671) ~[paper-1.20.4.jar:git-Paper-409]
	at net.minecraft.server.MinecraftServer.loadLevel(MinecraftServer.java:431) ~[paper-1.20.4.jar:git-Paper-409]
	at net.minecraft.server.dedicated.DedicatedServer.initServer(DedicatedServer.java:308) ~[paper-1.20.4.jar:git-Paper-409]
	at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1131) ~[paper-1.20.4.jar:git-Paper-409]
	at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:319) ~[paper-1.20.4.jar:git-Paper-409]
	at java.lang.Thread.run(Thread.java:1583) ~[?:?]
[00:59:29] [Server thread/INFO]: [PWarp] Disabling PWarp v3.0.4
[00:59:29] [Server thread/INFO]: [PWarp] PWarp has been disabled!