Fix non-default mod settings allowing for duplicate freestyle mod selection in multiplayer

osu.Game.Tests/Mods/ModUtilsTest.cs

@@ -7,8 +7,10 @@
 using Moq;
 using NUnit.Framework;
 using NUnit.Framework.Legacy;
+using osu.Framework.Bindables;
 using osu.Framework.Extensions.TypeExtensions;
 using osu.Framework.Localisation;
+using osu.Game.Configuration;
 using osu.Game.Online.Rooms;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Catch;
@@ -33,6 +35,17 @@ public void TestModIsNotCompatibleWithItself()
             Assert.That(invalid, Is.EquivalentTo(new[] { mod.Object }));
         }
 
+        [Test]
+        public void TestModIsNotCompatibleWithItselfEvenIfSettingsDiffer()
+        {
+            var mod1 = new Mock<CustomMod3>();
+            var mod2 = new Mock<CustomMod3>();
+            mod2.Setup(m => m.Setting).Returns(new BindableBool(true));
+
+            Assert.That(ModUtils.CheckCompatibleSet(new[] { mod1.Object, mod2.Object }, out var invalid), Is.False);
+            Assert.That(invalid, Is.EquivalentTo(new[] { mod2.Object }));
+        }
+
         [Test]
         public void TestModIsCompatibleByItself()
         {
@@ -397,6 +410,12 @@ public abstract class CustomMod2 : Mod, IModCompatibilitySpecification
         {
         }
 
+        public abstract class CustomMod3 : Mod, IModCompatibilitySpecification
+        {
+            [SettingSource("Setting")]
+            public virtual BindableBool Setting { get; } = new BindableBool();
+        }
+
         private class InvalidMultiplayerMod : Mod
         {
             public override string Name => string.Empty;

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSubScreen.cs

@@ -330,6 +330,33 @@ public void TestModSelectOverlay()
             AddAssert("score multiplier = 1.20", () => this.ChildrenOfType<RankingInformationDisplay>().Single().ModMultiplier.Value, () => Is.EqualTo(1.2).Within(0.01));
         }
 
+        [Test]
+        public void TestModSelectOverlayNonDefaultSettings()
+        {
+            AddStep("add playlist item", () =>
+            {
+                room.Playlist =
+                [
+                    new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
+                    {
+                        RulesetID = new OsuRuleset().RulesetInfo.OnlineID,
+                        RequiredMods =
+                        [
+                            new APIMod(new OsuModSuddenDeath { FailOnSliderTail = { Value = true } }),
+                        ],
+                        AllowedMods = [],
+                        Freestyle = true
+                    }
+                ];
+            });
+            ClickButtonWhenEnabled<MultiplayerMatchSettingsOverlay.CreateOrUpdateButton>();
+
+            AddUntilStep("wait for join", () => RoomJoined);
+
+            ClickButtonWhenEnabled<UserModSelectButton>();
+            AddAssert("sudden death not visible", () => this.ChildrenOfType<MultiplayerUserModSelectOverlay>().Single().ChildrenOfType<ModPanel>().Single(m => m.Mod is ModSuddenDeath).Visible == false);
+        }
+
         [Test]
         public void TestChangeSettingsButtonVisibleForHost()
         {

osu.Game/Utils/ModUtils.cs

@@ -63,7 +63,7 @@ public static bool CheckCompatibleSet(IEnumerable<Mod> combination, [NotNullWhen
                 {
                     var m = mods[j];
 
-                    if (candidate.Equals(m))
+                    if (candidate.GetType() == m.GetType())
                     {
                         invalidMods ??= new List<Mod>();
                         invalidMods.Add(m);