From 4cb58fbe474c3c0663fb19284ae6de23ca53b2d4 Mon Sep 17 00:00:00 2001
From: Dan Balasescu <smoogipoo@smgi.me>
Date: Mon, 1 Jul 2024 14:58:32 +0900
Subject: [PATCH 1/9] Add failing test

---
 .../Mods/TestSceneManiaModInvert.cs           | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
index 2977241dc6..95fe73db50 100644
--- a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
+++ b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
@@ -2,6 +2,8 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using NUnit.Framework;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets.Mania.Mods;
 using osu.Game.Tests.Visual;
 
@@ -17,5 +19,22 @@ public void TestInversion() => CreateModTest(new ModTestData
             Mod = new ManiaModInvert(),
             PassCondition = () => Player.ScoreProcessor.JudgedHits >= 2
         });
+
+        [Test]
+        public void TestBreaksPreservedOnOriginalBeatmap()
+        {
+            var beatmap = CreateBeatmap(new ManiaRuleset().RulesetInfo);
+            beatmap.Breaks.Clear();
+            beatmap.Breaks.Add(new BreakPeriod(0, 1000));
+
+            var workingBeatmap = new FlatWorkingBeatmap(beatmap);
+
+            var playableWithInvert = workingBeatmap.GetPlayableBeatmap(new ManiaRuleset().RulesetInfo, new[] { new ManiaModInvert() });
+            Assert.That(playableWithInvert.Breaks.Count, Is.Zero);
+
+            var playableWithoutInvert = workingBeatmap.GetPlayableBeatmap(new ManiaRuleset().RulesetInfo);
+            Assert.That(playableWithoutInvert.Breaks.Count, Is.Not.Zero);
+            Assert.That(playableWithoutInvert.Breaks[0], Is.EqualTo(new BreakPeriod(0, 1000)));
+        }
     }
 }

From f942595829336ce1334ec86b88fb04be9068412c Mon Sep 17 00:00:00 2001
From: Dan Balasescu <smoogipoo@smgi.me>
Date: Mon, 1 Jul 2024 14:58:53 +0900
Subject: [PATCH 2/9] Fix `ManiaModInvert` permanently messing up the beatmap

---
 osu.Game/Beatmaps/BeatmapConverter.cs                | 5 +++++
 osu.Game/Beatmaps/IBeatmap.cs                        | 2 +-
 osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs | 7 ++++++-
 osu.Game/Screens/Edit/EditorBeatmap.cs               | 6 +++++-
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index b68c80d4b3..0ec8eab5d8 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -7,6 +7,8 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
+using osu.Framework.Bindables;
+using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Objects;
 
@@ -49,6 +51,9 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             original.BeatmapInfo = original.BeatmapInfo.Clone();
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
 
+            // Used in osu!mania conversion.
+            original.Breaks = new BindableList<BreakPeriod>(original.Breaks);
+
             return ConvertBeatmap(original, cancellationToken);
         }
 
diff --git a/osu.Game/Beatmaps/IBeatmap.cs b/osu.Game/Beatmaps/IBeatmap.cs
index 072e246a36..d8a2560559 100644
--- a/osu.Game/Beatmaps/IBeatmap.cs
+++ b/osu.Game/Beatmaps/IBeatmap.cs
@@ -41,7 +41,7 @@ public interface IBeatmap
         /// <summary>
         /// The breaks in this beatmap.
         /// </summary>
-        BindableList<BreakPeriod> Breaks { get; }
+        BindableList<BreakPeriod> Breaks { get; set; }
 
         /// <summary>
         /// All lines from the [Events] section which aren't handled in the encoding process yet.
diff --git a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
index 4c6a4cc9c2..97037302c6 100644
--- a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
@@ -328,7 +328,12 @@ public BeatmapDifficulty Difficulty
                 set => baseBeatmap.Difficulty = value;
             }
 
-            public BindableList<BreakPeriod> Breaks => baseBeatmap.Breaks;
+            public BindableList<BreakPeriod> Breaks
+            {
+                get => baseBeatmap.Breaks;
+                set => baseBeatmap.Breaks = value;
+            }
+
             public List<string> UnhandledEventLines => baseBeatmap.UnhandledEventLines;
 
             public double TotalBreakTime => baseBeatmap.TotalBreakTime;
diff --git a/osu.Game/Screens/Edit/EditorBeatmap.cs b/osu.Game/Screens/Edit/EditorBeatmap.cs
index ae0fd9130f..331da51888 100644
--- a/osu.Game/Screens/Edit/EditorBeatmap.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmap.cs
@@ -172,7 +172,11 @@ public ControlPointInfo ControlPointInfo
             set => PlayableBeatmap.ControlPointInfo = value;
         }
 
-        public BindableList<BreakPeriod> Breaks => PlayableBeatmap.Breaks;
+        public BindableList<BreakPeriod> Breaks
+        {
+            get => PlayableBeatmap.Breaks;
+            set => PlayableBeatmap.Breaks = value;
+        }
 
         public List<string> UnhandledEventLines => PlayableBeatmap.UnhandledEventLines;
 

From 005af280f2ee8c05adb0bc0b5609b52eb40900fc Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Tue, 2 Jul 2024 11:13:20 +0900
Subject: [PATCH 3/9] Isolate bindable breaks list to `EditorBeatmap`

---
 .../TestSceneEditorBeatmapProcessor.cs        | 85 +++++++++++--------
 osu.Game/Beatmaps/Beatmap.cs                  |  3 +-
 osu.Game/Beatmaps/BeatmapConverter.cs         |  4 +-
 osu.Game/Beatmaps/IBeatmap.cs                 |  3 +-
 .../Difficulty/DifficultyCalculator.cs        |  3 +-
 osu.Game/Screens/Edit/EditorBeatmap.cs        |  8 +-
 .../Screens/Edit/EditorBeatmapProcessor.cs    |  6 +-
 7 files changed, 66 insertions(+), 46 deletions(-)

diff --git a/osu.Game.Tests/Editing/TestSceneEditorBeatmapProcessor.cs b/osu.Game.Tests/Editing/TestSceneEditorBeatmapProcessor.cs
index 1a3f0aa3df..251099c0e2 100644
--- a/osu.Game.Tests/Editing/TestSceneEditorBeatmapProcessor.cs
+++ b/osu.Game.Tests/Editing/TestSceneEditorBeatmapProcessor.cs
@@ -21,10 +21,11 @@ public void TestEmptyBeatmap()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
-            };
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -38,14 +39,15 @@ public void TestSingleObjectBeatmap()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -59,15 +61,16 @@ public void TestTwoObjectsCloseTogether()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
                     new HitCircle { StartTime = 2000 },
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -81,14 +84,15 @@ public void TestHoldNote()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new ManiaRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HoldNote { StartTime = 1000, Duration = 10000 },
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new ManiaRuleset());
             beatmapProcessor.PreProcess();
@@ -102,16 +106,17 @@ public void TestHoldNoteWithOverlappingNote()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new ManiaRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HoldNote { StartTime = 1000, Duration = 10000 },
                     new Note { StartTime = 2000 },
                     new Note { StartTime = 12000 },
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new ManiaRuleset());
             beatmapProcessor.PreProcess();
@@ -125,15 +130,16 @@ public void TestTwoObjectsFarApart()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
                     new HitCircle { StartTime = 5000 },
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -152,9 +158,10 @@ public void TestBreaksAreFused()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -165,7 +172,7 @@ public void TestBreaksAreFused()
                     new BreakPeriod(1200, 4000),
                     new BreakPeriod(5200, 8000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -184,9 +191,10 @@ public void TestBreaksAreSplit()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -197,7 +205,7 @@ public void TestBreaksAreSplit()
                 {
                     new BreakPeriod(1200, 8000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -218,9 +226,10 @@ public void TestBreaksAreNudged()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1100 },
@@ -230,7 +239,7 @@ public void TestBreaksAreNudged()
                 {
                     new BreakPeriod(1200, 8000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -249,9 +258,10 @@ public void TestManualBreaksAreNotFused()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -262,7 +272,7 @@ public void TestManualBreaksAreNotFused()
                     new ManualBreakPeriod(1200, 4000),
                     new ManualBreakPeriod(5200, 8000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -283,9 +293,10 @@ public void TestManualBreaksAreSplit()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -296,7 +307,7 @@ public void TestManualBreaksAreSplit()
                 {
                     new ManualBreakPeriod(1200, 8000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -317,9 +328,10 @@ public void TestManualBreaksAreNotNudged()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -329,7 +341,7 @@ public void TestManualBreaksAreNotNudged()
                 {
                     new ManualBreakPeriod(1200, 8800),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -348,9 +360,10 @@ public void TestBreaksAtEndOfBeatmapAreRemoved()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -360,7 +373,7 @@ public void TestBreaksAtEndOfBeatmapAreRemoved()
                 {
                     new BreakPeriod(10000, 15000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -374,9 +387,10 @@ public void TestManualBreaksAtEndOfBeatmapAreRemoved()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 1000 },
@@ -386,7 +400,7 @@ public void TestManualBreaksAtEndOfBeatmapAreRemoved()
                 {
                     new ManualBreakPeriod(10000, 15000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -400,9 +414,10 @@ public void TestManualBreaksAtEndOfBeatmapAreRemovedCorrectlyEvenWithConcurrentO
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HoldNote { StartTime = 1000, EndTime = 20000 },
@@ -412,7 +427,7 @@ public void TestManualBreaksAtEndOfBeatmapAreRemovedCorrectlyEvenWithConcurrentO
                 {
                     new ManualBreakPeriod(10000, 15000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -426,9 +441,10 @@ public void TestBreaksAtStartOfBeatmapAreRemoved()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 10000 },
@@ -438,7 +454,7 @@ public void TestBreaksAtStartOfBeatmapAreRemoved()
                 {
                     new BreakPeriod(0, 9000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
@@ -452,9 +468,10 @@ public void TestManualBreaksAtStartOfBeatmapAreRemoved()
         {
             var controlPoints = new ControlPointInfo();
             controlPoints.Add(0, new TimingControlPoint { BeatLength = 500 });
-            var beatmap = new Beatmap
+            var beatmap = new EditorBeatmap(new Beatmap
             {
                 ControlPointInfo = controlPoints,
+                BeatmapInfo = { Ruleset = new OsuRuleset().RulesetInfo },
                 HitObjects =
                 {
                     new HitCircle { StartTime = 10000 },
@@ -464,7 +481,7 @@ public void TestManualBreaksAtStartOfBeatmapAreRemoved()
                 {
                     new ManualBreakPeriod(0, 9000),
                 }
-            };
+            });
 
             var beatmapProcessor = new EditorBeatmapProcessor(beatmap, new OsuRuleset());
             beatmapProcessor.PreProcess();
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index 510410bc09..ae77e4adcf 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -8,7 +8,6 @@
 using System.Linq;
 using osu.Game.Beatmaps.ControlPoints;
 using Newtonsoft.Json;
-using osu.Framework.Bindables;
 using osu.Game.IO.Serialization.Converters;
 
 namespace osu.Game.Beatmaps
@@ -62,7 +61,7 @@ public Beatmap()
 
         public ControlPointInfo ControlPointInfo { get; set; } = new ControlPointInfo();
 
-        public BindableList<BreakPeriod> Breaks { get; set; } = new BindableList<BreakPeriod>();
+        public List<BreakPeriod> Breaks { get; set; } = new List<BreakPeriod>();
 
         public List<string> UnhandledEventLines { get; set; } = new List<string>();
 
diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index 0ec8eab5d8..676eb1b159 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -7,8 +7,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
-using osu.Framework.Bindables;
-using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Objects;
 
@@ -52,7 +50,7 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
 
             // Used in osu!mania conversion.
-            original.Breaks = new BindableList<BreakPeriod>(original.Breaks);
+            original.Breaks = original.Breaks.ToList();
 
             return ConvertBeatmap(original, cancellationToken);
         }
diff --git a/osu.Game/Beatmaps/IBeatmap.cs b/osu.Game/Beatmaps/IBeatmap.cs
index d8a2560559..0d39c1f977 100644
--- a/osu.Game/Beatmaps/IBeatmap.cs
+++ b/osu.Game/Beatmaps/IBeatmap.cs
@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using osu.Framework.Bindables;
 using osu.Game.Beatmaps.ControlPoints;
 using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets.Objects;
@@ -41,7 +40,7 @@ public interface IBeatmap
         /// <summary>
         /// The breaks in this beatmap.
         /// </summary>
-        BindableList<BreakPeriod> Breaks { get; set; }
+        List<BreakPeriod> Breaks { get; set; }
 
         /// <summary>
         /// All lines from the [Events] section which aren't handled in the encoding process yet.
diff --git a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
index 97037302c6..722263c58e 100644
--- a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
@@ -9,7 +9,6 @@
 using System.Threading;
 using JetBrains.Annotations;
 using osu.Framework.Audio.Track;
-using osu.Framework.Bindables;
 using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.ControlPoints;
@@ -328,7 +327,7 @@ public BeatmapDifficulty Difficulty
                 set => baseBeatmap.Difficulty = value;
             }
 
-            public BindableList<BreakPeriod> Breaks
+            public List<BreakPeriod> Breaks
             {
                 get => baseBeatmap.Breaks;
                 set => baseBeatmap.Breaks = value;
diff --git a/osu.Game/Screens/Edit/EditorBeatmap.cs b/osu.Game/Screens/Edit/EditorBeatmap.cs
index 331da51888..1ebd2e6337 100644
--- a/osu.Game/Screens/Edit/EditorBeatmap.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmap.cs
@@ -110,6 +110,9 @@ public EditorBeatmap(IBeatmap playableBeatmap, ISkin beatmapSkin = null, Beatmap
             foreach (var obj in HitObjects)
                 trackStartTime(obj);
 
+            Breaks = new BindableList<BreakPeriod>(playableBeatmap.Breaks);
+            Breaks.BindCollectionChanged((_, _) => playableBeatmap.Breaks = Breaks.ToList());
+
             PreviewTime = new BindableInt(BeatmapInfo.Metadata.PreviewTime);
             PreviewTime.BindValueChanged(s =>
             {
@@ -172,7 +175,9 @@ public ControlPointInfo ControlPointInfo
             set => PlayableBeatmap.ControlPointInfo = value;
         }
 
-        public BindableList<BreakPeriod> Breaks
+        public readonly BindableList<BreakPeriod> Breaks;
+
+        List<BreakPeriod> IBeatmap.Breaks
         {
             get => PlayableBeatmap.Breaks;
             set => PlayableBeatmap.Breaks = value;
@@ -191,6 +196,7 @@ public BindableList<BreakPeriod> Breaks
         public IBeatmap Clone() => (EditorBeatmap)MemberwiseClone();
 
         private IList mutableHitObjects => (IList)PlayableBeatmap.HitObjects;
+        private IList mutableBreaks => (IList)PlayableBeatmap.Breaks;
 
         private readonly List<HitObject> batchPendingInserts = new List<HitObject>();
 
diff --git a/osu.Game/Screens/Edit/EditorBeatmapProcessor.cs b/osu.Game/Screens/Edit/EditorBeatmapProcessor.cs
index 99c8c3572b..377e978c4a 100644
--- a/osu.Game/Screens/Edit/EditorBeatmapProcessor.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmapProcessor.cs
@@ -12,11 +12,13 @@ namespace osu.Game.Screens.Edit
 {
     public class EditorBeatmapProcessor : IBeatmapProcessor
     {
-        public IBeatmap Beatmap { get; }
+        public EditorBeatmap Beatmap { get; }
+
+        IBeatmap IBeatmapProcessor.Beatmap => Beatmap;
 
         private readonly IBeatmapProcessor? rulesetBeatmapProcessor;
 
-        public EditorBeatmapProcessor(IBeatmap beatmap, Ruleset ruleset)
+        public EditorBeatmapProcessor(EditorBeatmap beatmap, Ruleset ruleset)
         {
             Beatmap = beatmap;
             rulesetBeatmapProcessor = ruleset.CreateBeatmapProcessor(beatmap);

From f694ae416eba180f03c55a0374018a2ccf53a593 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Tue, 2 Jul 2024 11:47:40 +0900
Subject: [PATCH 4/9] Fix typo in xmldoc

---
 osu.Game/Beatmaps/IBeatmap.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/osu.Game/Beatmaps/IBeatmap.cs b/osu.Game/Beatmaps/IBeatmap.cs
index 0d39c1f977..176738489a 100644
--- a/osu.Game/Beatmaps/IBeatmap.cs
+++ b/osu.Game/Beatmaps/IBeatmap.cs
@@ -44,7 +44,7 @@ public interface IBeatmap
 
         /// <summary>
         /// All lines from the [Events] section which aren't handled in the encoding process yet.
-        /// These lines shoule be written out to the beatmap file on save or export.
+        /// These lines should be written out to the beatmap file on save or export.
         /// </summary>
         List<string> UnhandledEventLines { get; }
 

From 2c3b411bb5e77696a29abf5fdeb873b1d72c47a7 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Tue, 2 Jul 2024 11:59:24 +0900
Subject: [PATCH 5/9] Change breaks list to `IReadOnlyList`

---
 .../Mods/TestSceneManiaModInvert.cs                        | 7 +++++--
 osu.Game/Beatmaps/Beatmap.cs                               | 6 ++++++
 osu.Game/Beatmaps/BeatmapConverter.cs                      | 7 +++----
 osu.Game/Beatmaps/IBeatmap.cs                              | 2 +-
 osu.Game/Database/LegacyBeatmapExporter.cs                 | 6 +++++-
 osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs       | 2 +-
 osu.Game/Screens/Edit/EditorBeatmap.cs                     | 2 +-
 7 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
index 95fe73db50..576b07265b 100644
--- a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
+++ b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System.Collections.Generic;
 using NUnit.Framework;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.Timing;
@@ -24,8 +25,10 @@ public void TestInversion() => CreateModTest(new ModTestData
         public void TestBreaksPreservedOnOriginalBeatmap()
         {
             var beatmap = CreateBeatmap(new ManiaRuleset().RulesetInfo);
-            beatmap.Breaks.Clear();
-            beatmap.Breaks.Add(new BreakPeriod(0, 1000));
+            var breaks = (List<BreakPeriod>)beatmap.Breaks;
+
+            breaks.Clear();
+            breaks.Add(new BreakPeriod(0, 1000));
 
             var workingBeatmap = new FlatWorkingBeatmap(beatmap);
 
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index ae77e4adcf..b185c1cd5a 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -61,6 +61,12 @@ public Beatmap()
 
         public ControlPointInfo ControlPointInfo { get; set; } = new ControlPointInfo();
 
+        IReadOnlyList<BreakPeriod> IBeatmap.Breaks
+        {
+            get => Breaks;
+            set => Breaks = new List<BreakPeriod>(value);
+        }
+
         public List<BreakPeriod> Breaks { get; set; } = new List<BreakPeriod>();
 
         public List<string> UnhandledEventLines { get; set; } = new List<string>();
diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index 676eb1b159..e62de3e69b 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -7,6 +7,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
+using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Objects;
 
@@ -49,9 +50,6 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             original.BeatmapInfo = original.BeatmapInfo.Clone();
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
 
-            // Used in osu!mania conversion.
-            original.Breaks = original.Breaks.ToList();
-
             return ConvertBeatmap(original, cancellationToken);
         }
 
@@ -68,7 +66,8 @@ protected virtual Beatmap<T> ConvertBeatmap(IBeatmap original, CancellationToken
             beatmap.BeatmapInfo = original.BeatmapInfo;
             beatmap.ControlPointInfo = original.ControlPointInfo;
             beatmap.HitObjects = convertHitObjects(original.HitObjects, original, cancellationToken).OrderBy(s => s.StartTime).ToList();
-            beatmap.Breaks = original.Breaks;
+            // Used in osu!mania conversion.
+            beatmap.Breaks = new List<BreakPeriod>(original.Breaks);
             beatmap.UnhandledEventLines = original.UnhandledEventLines;
 
             return beatmap;
diff --git a/osu.Game/Beatmaps/IBeatmap.cs b/osu.Game/Beatmaps/IBeatmap.cs
index 176738489a..151edc9ad8 100644
--- a/osu.Game/Beatmaps/IBeatmap.cs
+++ b/osu.Game/Beatmaps/IBeatmap.cs
@@ -40,7 +40,7 @@ public interface IBeatmap
         /// <summary>
         /// The breaks in this beatmap.
         /// </summary>
-        List<BreakPeriod> Breaks { get; set; }
+        IReadOnlyList<BreakPeriod> Breaks { get; set; }
 
         /// <summary>
         /// All lines from the [Events] section which aren't handled in the encoding process yet.
diff --git a/osu.Game/Database/LegacyBeatmapExporter.cs b/osu.Game/Database/LegacyBeatmapExporter.cs
index 17c2c8c88d..62f6f5d30d 100644
--- a/osu.Game/Database/LegacyBeatmapExporter.cs
+++ b/osu.Game/Database/LegacyBeatmapExporter.cs
@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
@@ -64,8 +65,11 @@ public LegacyBeatmapExporter(Storage storage)
             foreach (var controlPoint in playableBeatmap.ControlPointInfo.AllControlPoints)
                 controlPoint.Time = Math.Floor(controlPoint.Time);
 
+            var breaks = new List<BreakPeriod>(playableBeatmap.Breaks.Count);
             for (int i = 0; i < playableBeatmap.Breaks.Count; i++)
-                playableBeatmap.Breaks[i] = new BreakPeriod(Math.Floor(playableBeatmap.Breaks[i].StartTime), Math.Floor(playableBeatmap.Breaks[i].EndTime));
+                breaks.Add(new BreakPeriod(Math.Floor(playableBeatmap.Breaks[i].StartTime), Math.Floor(playableBeatmap.Breaks[i].EndTime)));
+
+            playableBeatmap.Breaks = breaks;
 
             foreach (var hitObject in playableBeatmap.HitObjects)
             {
diff --git a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
index 722263c58e..7262b9d1a8 100644
--- a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
@@ -327,7 +327,7 @@ public BeatmapDifficulty Difficulty
                 set => baseBeatmap.Difficulty = value;
             }
 
-            public List<BreakPeriod> Breaks
+            public IReadOnlyList<BreakPeriod> Breaks
             {
                 get => baseBeatmap.Breaks;
                 set => baseBeatmap.Breaks = value;
diff --git a/osu.Game/Screens/Edit/EditorBeatmap.cs b/osu.Game/Screens/Edit/EditorBeatmap.cs
index 1ebd2e6337..cc1d820427 100644
--- a/osu.Game/Screens/Edit/EditorBeatmap.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmap.cs
@@ -177,7 +177,7 @@ public ControlPointInfo ControlPointInfo
 
         public readonly BindableList<BreakPeriod> Breaks;
 
-        List<BreakPeriod> IBeatmap.Breaks
+        IReadOnlyList<BreakPeriod> IBeatmap.Breaks
         {
             get => PlayableBeatmap.Breaks;
             set => PlayableBeatmap.Breaks = value;

From f69bc40a4b465a6f6902d2038fcf824fb7b638bb Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Tue, 2 Jul 2024 12:07:13 +0900
Subject: [PATCH 6/9] Move break cloning back to non-virtual method

---
 osu.Game/Beatmaps/BeatmapConverter.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index e62de3e69b..5fd20d5aff 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -49,6 +49,8 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             // Can potentially be removed after `Beatmap.Difficulty` doesn't save back to `Beatmap.BeatmapInfo`.
             original.BeatmapInfo = original.BeatmapInfo.Clone();
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
+            // Used in osu!mania conversion.
+            original.Breaks = new List<BreakPeriod>(original.Breaks);
 
             return ConvertBeatmap(original, cancellationToken);
         }
@@ -66,8 +68,6 @@ protected virtual Beatmap<T> ConvertBeatmap(IBeatmap original, CancellationToken
             beatmap.BeatmapInfo = original.BeatmapInfo;
             beatmap.ControlPointInfo = original.ControlPointInfo;
             beatmap.HitObjects = convertHitObjects(original.HitObjects, original, cancellationToken).OrderBy(s => s.StartTime).ToList();
-            // Used in osu!mania conversion.
-            beatmap.Breaks = new List<BreakPeriod>(original.Breaks);
             beatmap.UnhandledEventLines = original.UnhandledEventLines;
 
             return beatmap;

From db847112149ae8e27d5960f2a7909acb5c91f480 Mon Sep 17 00:00:00 2001
From: Dan Balasescu <smoogipoo@smgi.me>
Date: Tue, 2 Jul 2024 12:16:10 +0900
Subject: [PATCH 7/9] Revert "Move break cloning back to non-virtual method"

This reverts commit f69bc40a4b465a6f6902d2038fcf824fb7b638bb.
---
 osu.Game/Beatmaps/BeatmapConverter.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index 5fd20d5aff..e62de3e69b 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -49,8 +49,6 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             // Can potentially be removed after `Beatmap.Difficulty` doesn't save back to `Beatmap.BeatmapInfo`.
             original.BeatmapInfo = original.BeatmapInfo.Clone();
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
-            // Used in osu!mania conversion.
-            original.Breaks = new List<BreakPeriod>(original.Breaks);
 
             return ConvertBeatmap(original, cancellationToken);
         }
@@ -68,6 +66,8 @@ protected virtual Beatmap<T> ConvertBeatmap(IBeatmap original, CancellationToken
             beatmap.BeatmapInfo = original.BeatmapInfo;
             beatmap.ControlPointInfo = original.ControlPointInfo;
             beatmap.HitObjects = convertHitObjects(original.HitObjects, original, cancellationToken).OrderBy(s => s.StartTime).ToList();
+            // Used in osu!mania conversion.
+            beatmap.Breaks = new List<BreakPeriod>(original.Breaks);
             beatmap.UnhandledEventLines = original.UnhandledEventLines;
 
             return beatmap;

From 04da1209f7d4caff3bc5689bea9c53d4eb2e1c0a Mon Sep 17 00:00:00 2001
From: Dan Balasescu <smoogipoo@smgi.me>
Date: Tue, 2 Jul 2024 12:16:11 +0900
Subject: [PATCH 8/9] Revert "Change breaks list to `IReadOnlyList`"

This reverts commit 2c3b411bb5e77696a29abf5fdeb873b1d72c47a7.
---
 .../Mods/TestSceneManiaModInvert.cs                        | 7 ++-----
 osu.Game/Beatmaps/Beatmap.cs                               | 6 ------
 osu.Game/Beatmaps/BeatmapConverter.cs                      | 7 ++++---
 osu.Game/Beatmaps/IBeatmap.cs                              | 2 +-
 osu.Game/Database/LegacyBeatmapExporter.cs                 | 6 +-----
 osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs       | 2 +-
 osu.Game/Screens/Edit/EditorBeatmap.cs                     | 2 +-
 7 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
index 576b07265b..95fe73db50 100644
--- a/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
+++ b/osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModInvert.cs
@@ -1,7 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-using System.Collections.Generic;
 using NUnit.Framework;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.Timing;
@@ -25,10 +24,8 @@ public void TestInversion() => CreateModTest(new ModTestData
         public void TestBreaksPreservedOnOriginalBeatmap()
         {
             var beatmap = CreateBeatmap(new ManiaRuleset().RulesetInfo);
-            var breaks = (List<BreakPeriod>)beatmap.Breaks;
-
-            breaks.Clear();
-            breaks.Add(new BreakPeriod(0, 1000));
+            beatmap.Breaks.Clear();
+            beatmap.Breaks.Add(new BreakPeriod(0, 1000));
 
             var workingBeatmap = new FlatWorkingBeatmap(beatmap);
 
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index b185c1cd5a..ae77e4adcf 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -61,12 +61,6 @@ public Beatmap()
 
         public ControlPointInfo ControlPointInfo { get; set; } = new ControlPointInfo();
 
-        IReadOnlyList<BreakPeriod> IBeatmap.Breaks
-        {
-            get => Breaks;
-            set => Breaks = new List<BreakPeriod>(value);
-        }
-
         public List<BreakPeriod> Breaks { get; set; } = new List<BreakPeriod>();
 
         public List<string> UnhandledEventLines { get; set; } = new List<string>();
diff --git a/osu.Game/Beatmaps/BeatmapConverter.cs b/osu.Game/Beatmaps/BeatmapConverter.cs
index e62de3e69b..676eb1b159 100644
--- a/osu.Game/Beatmaps/BeatmapConverter.cs
+++ b/osu.Game/Beatmaps/BeatmapConverter.cs
@@ -7,7 +7,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
-using osu.Game.Beatmaps.Timing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Objects;
 
@@ -50,6 +49,9 @@ public IBeatmap Convert(CancellationToken cancellationToken = default)
             original.BeatmapInfo = original.BeatmapInfo.Clone();
             original.ControlPointInfo = original.ControlPointInfo.DeepClone();
 
+            // Used in osu!mania conversion.
+            original.Breaks = original.Breaks.ToList();
+
             return ConvertBeatmap(original, cancellationToken);
         }
 
@@ -66,8 +68,7 @@ protected virtual Beatmap<T> ConvertBeatmap(IBeatmap original, CancellationToken
             beatmap.BeatmapInfo = original.BeatmapInfo;
             beatmap.ControlPointInfo = original.ControlPointInfo;
             beatmap.HitObjects = convertHitObjects(original.HitObjects, original, cancellationToken).OrderBy(s => s.StartTime).ToList();
-            // Used in osu!mania conversion.
-            beatmap.Breaks = new List<BreakPeriod>(original.Breaks);
+            beatmap.Breaks = original.Breaks;
             beatmap.UnhandledEventLines = original.UnhandledEventLines;
 
             return beatmap;
diff --git a/osu.Game/Beatmaps/IBeatmap.cs b/osu.Game/Beatmaps/IBeatmap.cs
index 151edc9ad8..176738489a 100644
--- a/osu.Game/Beatmaps/IBeatmap.cs
+++ b/osu.Game/Beatmaps/IBeatmap.cs
@@ -40,7 +40,7 @@ public interface IBeatmap
         /// <summary>
         /// The breaks in this beatmap.
         /// </summary>
-        IReadOnlyList<BreakPeriod> Breaks { get; set; }
+        List<BreakPeriod> Breaks { get; set; }
 
         /// <summary>
         /// All lines from the [Events] section which aren't handled in the encoding process yet.
diff --git a/osu.Game/Database/LegacyBeatmapExporter.cs b/osu.Game/Database/LegacyBeatmapExporter.cs
index 62f6f5d30d..17c2c8c88d 100644
--- a/osu.Game/Database/LegacyBeatmapExporter.cs
+++ b/osu.Game/Database/LegacyBeatmapExporter.cs
@@ -2,7 +2,6 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Text;
@@ -65,11 +64,8 @@ public LegacyBeatmapExporter(Storage storage)
             foreach (var controlPoint in playableBeatmap.ControlPointInfo.AllControlPoints)
                 controlPoint.Time = Math.Floor(controlPoint.Time);
 
-            var breaks = new List<BreakPeriod>(playableBeatmap.Breaks.Count);
             for (int i = 0; i < playableBeatmap.Breaks.Count; i++)
-                breaks.Add(new BreakPeriod(Math.Floor(playableBeatmap.Breaks[i].StartTime), Math.Floor(playableBeatmap.Breaks[i].EndTime)));
-
-            playableBeatmap.Breaks = breaks;
+                playableBeatmap.Breaks[i] = new BreakPeriod(Math.Floor(playableBeatmap.Breaks[i].StartTime), Math.Floor(playableBeatmap.Breaks[i].EndTime));
 
             foreach (var hitObject in playableBeatmap.HitObjects)
             {
diff --git a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
index 7262b9d1a8..722263c58e 100644
--- a/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
+++ b/osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs
@@ -327,7 +327,7 @@ public BeatmapDifficulty Difficulty
                 set => baseBeatmap.Difficulty = value;
             }
 
-            public IReadOnlyList<BreakPeriod> Breaks
+            public List<BreakPeriod> Breaks
             {
                 get => baseBeatmap.Breaks;
                 set => baseBeatmap.Breaks = value;
diff --git a/osu.Game/Screens/Edit/EditorBeatmap.cs b/osu.Game/Screens/Edit/EditorBeatmap.cs
index cc1d820427..1ebd2e6337 100644
--- a/osu.Game/Screens/Edit/EditorBeatmap.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmap.cs
@@ -177,7 +177,7 @@ public ControlPointInfo ControlPointInfo
 
         public readonly BindableList<BreakPeriod> Breaks;
 
-        IReadOnlyList<BreakPeriod> IBeatmap.Breaks
+        List<BreakPeriod> IBeatmap.Breaks
         {
             get => PlayableBeatmap.Breaks;
             set => PlayableBeatmap.Breaks = value;

From 31edca866c6d921cc0f628f4074aece1a63f8c75 Mon Sep 17 00:00:00 2001
From: Dan Balasescu <smoogipoo@smgi.me>
Date: Tue, 2 Jul 2024 12:21:24 +0900
Subject: [PATCH 9/9] Remove unused code

---
 osu.Game/Screens/Edit/EditorBeatmap.cs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/osu.Game/Screens/Edit/EditorBeatmap.cs b/osu.Game/Screens/Edit/EditorBeatmap.cs
index 1ebd2e6337..c8592b5bea 100644
--- a/osu.Game/Screens/Edit/EditorBeatmap.cs
+++ b/osu.Game/Screens/Edit/EditorBeatmap.cs
@@ -196,7 +196,6 @@ List<BreakPeriod> IBeatmap.Breaks
         public IBeatmap Clone() => (EditorBeatmap)MemberwiseClone();
 
         private IList mutableHitObjects => (IList)PlayableBeatmap.HitObjects;
-        private IList mutableBreaks => (IList)PlayableBeatmap.Breaks;
 
         private readonly List<HitObject> batchPendingInserts = new List<HitObject>();