Apply fix from @punchready

CHANGELOG.md

@@ -18,6 +18,7 @@ This is the rolling changelog for TShock for Terraria. Use past tense when addin
 * Updated server startup language to be more clear when encountering a fatal startup error. Now, the server gives more context as to what happened so that there's a better chance of people being able to help themselves. (@hakusaro)
 * Added `-worldevil <type>` command line argument (@NotGeri)
 * Added PlayerHasBuildPermission hook to PlayerHooks. (@AnzhelikaO, @Killia0)
+* Prevent Server Broadcast to display prefix without a message. (@PackmanDude)
 
 ## TShock 4.5.17
 * Fixed duplicate characters (twins) after repeatedly logging in as the same character due to connection not being immediately closed during `NetHooks_NameCollision`. (@gohjoseph)

TShockAPI/Commands.cs

@@ -1954,6 +1954,8 @@ namespace TShockAPI
 		}
 
 		private static void Broadcast(CommandArgs args)
+		{
+			if (args.Parameters.Count > 0)
 			{
 				string message = string.Join(" ", args.Parameters);
 
@@ -1962,6 +1964,7 @@ namespace TShockAPI
 					Convert.ToByte(TShock.Config.Settings.BroadcastRGB[0]), Convert.ToByte(TShock.Config.Settings.BroadcastRGB[1]),
 					Convert.ToByte(TShock.Config.Settings.BroadcastRGB[2]));
 			}
+		}
 
 		private static void Off(CommandArgs args)
 		{