make Groups more resilient

src/webpage/direct.ts

@@ -519,6 +519,7 @@ class Group extends Channel {
 	}
 	addRec(user: User) {
 		this.users.push(user);
+		this.users = [...new Set(this.users)];
 		if (this.localuser.channelfocus === this) {
 			this.localuser.memberListUpdate();
 		}

src/webpage/localuser.ts

@@ -1167,9 +1167,9 @@ class Localuser {
 		}
 		elms.set("online", []);
 		elms.set("offline", []);
-		const members = new Set<User | Member>(guild.members);
+		let members = new Set<User | Member>(guild.members);
 		if (channel instanceof Group) {
-			channel.users.forEach((user) => members.add(user));
+			members = new Set(channel.users);
 			members.add(this.user);
 		}
 		members.forEach((member) => {