Get the max name length from the FriendAdders

src/main/java/io/github/gaming32/worldhost/gui/screen/AddFriendScreen.java

@@ -84,7 +84,7 @@ protected void init() {
         GameProfileCache.setUsesAuthentication(true); // This makes non-existent users return an empty value instead of an offline mode fallback.
 
         nameField = addRenderableWidget(new EditBox(font, width / 2 - 100, 66, 200, 20, nameField, FRIEND_USERNAME_TEXT));
-        nameField.setMaxLength(36);
+        friendAdders.stream().mapToInt(FriendAdder::maxValidNameLength).max().ifPresent(nameField::setMaxLength);
         //#if MC >= 1.19.4
         setInitialFocus(nameField);
         //#else
@@ -95,6 +95,7 @@ protected void init() {
             userList.clearUsers();
             final List<FriendAdder> delayedAdders = new ArrayList<>();
             for (final FriendAdder adder : friendAdders) {
+                if (name.length() > adder.maxValidNameLength()) continue;
                 if (adder.delayLookup(name)) {
                     delayedAdders.add(adder);
                 } else {

src/main/java/io/github/gaming32/worldhost/plugin/FriendAdder.java

@@ -15,5 +15,16 @@ public interface FriendAdder {
      */
     void searchFriends(String name, int maxResults, Consumer<FriendListFriend> friendConsumer);
 
+    /**
+     * Determine whether searching name is expensive to look up and should be delayed until the user has quit typing.
+     * @param name The name to check for delay requirements.
+     * @return Whether to delay the search until the user has quit typing.
+     */
     boolean delayLookup(String name);
+
+    /**
+     * The maximum length for a valid username. Names longer than this will not be given to this {@link FriendAdder}.
+     * @return The maximum valid username length;
+     */
+    int maxValidNameLength();
 }

src/main/java/io/github/gaming32/worldhost/plugin/vanilla/WorldHostFriendAdder.java

@@ -43,4 +43,9 @@ public void searchFriends(String name, int maxResults, Consumer<FriendListFriend
     public boolean delayLookup(String name) {
         return !VALID_UUID.matcher(name).matches() && !name.startsWith("o:");
     }
+
+    @Override
+    public int maxValidNameLength() {
+        return 36;
+    }
 }