diff --git a/osu.Game.Rulesets.Karaoke.Tests/IO/Stores/BaseGlyphStoreTest.cs b/osu.Game.Rulesets.Karaoke.Tests/IO/Stores/BaseGlyphStoreTest.cs
index 0a0e776bd..1e151bcba 100644
--- a/osu.Game.Rulesets.Karaoke.Tests/IO/Stores/BaseGlyphStoreTest.cs
+++ b/osu.Game.Rulesets.Karaoke.Tests/IO/Stores/BaseGlyphStoreTest.cs
@@ -22,7 +22,7 @@ public abstract class BaseGlyphStoreTest<TGlyphStore> where TGlyphStore : IGlyph
         protected void OneTimeSetUp()
         {
             // create and load glyph store.
-            var fontResourceStore = new NamespacedResourceStore<byte[]>(TestResources.GetStore(), $"Resources.Testing.Fonts.Fnt.OpenSans");
+            var fontResourceStore = new NamespacedResourceStore<byte[]>(TestResources.GetStore(), "Resources.Testing.Fonts.Fnt.OpenSans");
             GlyphStore = new GlyphStore(fontResourceStore, FontName);
             GlyphStore.LoadFontAsync().Wait();
 
diff --git a/osu.Game.Rulesets.Karaoke.Tests/Overlays/TestSceneOverlayColourProvider.cs b/osu.Game.Rulesets.Karaoke.Tests/Overlays/TestSceneOverlayColourProvider.cs
index 9cb13ece1..5424b29e1 100644
--- a/osu.Game.Rulesets.Karaoke.Tests/Overlays/TestSceneOverlayColourProvider.cs
+++ b/osu.Game.Rulesets.Karaoke.Tests/Overlays/TestSceneOverlayColourProvider.cs
@@ -1,6 +1,7 @@
 // Copyright (c) andy840119 <andy840119@gmail.com>. Licensed under the GPL Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Allocation;
@@ -64,6 +65,23 @@ public void ShowWithNoFetch()
 
             Schedule(() =>
             {
+                var columns = colourName.Select(c => new TitleTableColumn(c)).OfType<TableColumn>().ToArray();
+                var content = providers.Select(provider =>
+                {
+                    if (provider == null)
+                        throw new ArgumentNullException(nameof(provider));
+
+                    return colourName.Select(c =>
+                    {
+                        var value = provider.GetType().GetProperty(c)?.GetValue(provider);
+                        if (value == null)
+                            throw new ArgumentNullException(nameof(value));
+
+                        var colour = (Color4)value;
+                        return new PreviewColourDrawable(colour);
+                    }).OfType<Drawable>();
+                }).To2DArray();
+
                 Child = new OsuScrollContainer(Direction.Horizontal)
                 {
                     RelativeSizeAxes = Axes.Both,
@@ -71,15 +89,8 @@ public void ShowWithNoFetch()
                     {
                         RelativeSizeAxes = Axes.Y,
                         AutoSizeAxes = Axes.X,
-                        Columns = colourName.Select(c => new TitleTableColumn(c)).ToArray(),
-                        Content = providers.Select(p =>
-                        {
-                            return colourName.Select(c =>
-                            {
-                                var colour = (Color4)p.GetType().GetProperty(c).GetValue(p);
-                                return new PreviewColourDrawable(colour);
-                            });
-                        }).To2DArray(),
+                        Columns = columns,
+                        Content = content,
                     }
                 };
             });
diff --git a/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/LrcDecoder.cs b/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/LrcDecoder.cs
index 7a974ee18..7e09c8c5b 100644
--- a/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/LrcDecoder.cs
+++ b/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/LrcDecoder.cs
@@ -19,7 +19,7 @@ public class LrcDecoder : Decoder<Beatmap>
         public static void Register()
         {
             // Lrc decoder looks like [mm:ss:__]
-            AddDecoder<Beatmap>("[", m => new LrcDecoder());
+            AddDecoder<Beatmap>("[", _ => new LrcDecoder());
         }
 
         protected override void ParseStreamInto(LineBufferedReader stream, Beatmap output)
diff --git a/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/NicoKaraDecoder.cs b/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/NicoKaraDecoder.cs
index a3fc19870..df5159141 100644
--- a/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/NicoKaraDecoder.cs
+++ b/osu.Game.Rulesets.Karaoke/Beatmaps/Formats/NicoKaraDecoder.cs
@@ -27,7 +27,7 @@ public class NicoKaraDecoder : Decoder<KaraokeSkin>
     {
         public static void Register()
         {
-            AddDecoder<KaraokeSkin>("<?xml version=", m => new NicoKaraDecoder());
+            AddDecoder<KaraokeSkin>("<?xml version=", _ => new NicoKaraDecoder());
         }
 
         protected override void ParseStreamInto(LineBufferedReader stream, KaraokeSkin output)
diff --git a/osu.Game.Rulesets.Karaoke/Difficulty/KaraokePerformanceCalculator.cs b/osu.Game.Rulesets.Karaoke/Difficulty/KaraokePerformanceCalculator.cs
index 85f16a951..f18bba2c0 100644
--- a/osu.Game.Rulesets.Karaoke/Difficulty/KaraokePerformanceCalculator.cs
+++ b/osu.Game.Rulesets.Karaoke/Difficulty/KaraokePerformanceCalculator.cs
@@ -45,9 +45,8 @@ public override double Calculate(Dictionary<string, double> categoryDifficulty =
 
             IEnumerable<Mod> scoreIncreaseMods = Ruleset.GetModsFor(ModType.DifficultyIncrease);
 
-            double scoreMultiplier = 1.0;
-            foreach (var m in mods.Where(m => !scoreIncreaseMods.Contains(m)))
-                scoreMultiplier *= m.ScoreMultiplier;
+            double scoreMultiplier = mods.Where(m => !scoreIncreaseMods.Contains(m))
+                                         .Aggregate(1.0, (current, m) => current * m.ScoreMultiplier);
 
             // Scale score up, so it's comparable to other keymods
             scaledScore *= 1.0 / scoreMultiplier;
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Components/ContextMenu/LyricLockContextMenu.cs b/osu.Game.Rulesets.Karaoke/Edit/Components/ContextMenu/LyricLockContextMenu.cs
index fc124ea30..d1f52f1fd 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Components/ContextMenu/LyricLockContextMenu.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Components/ContextMenu/LyricLockContextMenu.cs
@@ -24,7 +24,7 @@ public LyricLockContextMenu(LyricManager manager, List<Lyric> lyrics, string nam
             Items = EnumUtils.GetValues<LockState>().Select(l => new OsuMenuItem(l.ToString(), anyLyricInLockState(l) ? MenuItemType.Highlighted : MenuItemType.Standard, () =>
             {
                 // change all selected lyric state.
-                lyrics.ForEach(lyric => manager.LockLyrics(lyrics, l));
+                manager.LockLyrics(lyrics, l);
             })).ToList();
 
             bool anyLyricInLockState(LockState lockState) => lyrics.Any(lyric => lyric.Lock == lockState);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Components/Menu/AutoFocusToEditLyricMenu.cs b/osu.Game.Rulesets.Karaoke/Edit/Components/Menu/AutoFocusToEditLyricMenu.cs
index dde207008..3bf634f7a 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Components/Menu/AutoFocusToEditLyricMenu.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Components/Menu/AutoFocusToEditLyricMenu.cs
@@ -32,13 +32,13 @@ public AutoFocusToEditLyricMenu(KaraokeRulesetLyricEditorConfigManager config, s
             config.BindWith(KaraokeRulesetLyricEditorSetting.AutoFocusToEditLyricSkipRows, bindableAutoFocusToEditLyricSkipRows);
 
             // mark disable as selected option.
-            bindableAutoFocusToEditLyric.BindValueChanged(e =>
+            bindableAutoFocusToEditLyric.BindValueChanged(_ =>
             {
                 updateSelectionState();
             }, true);
 
             // mark line as selected option.
-            bindableAutoFocusToEditLyricSkipRows.BindValueChanged(e =>
+            bindableAutoFocusToEditLyricSkipRows.BindValueChanged(_ =>
             {
                 updateSelectionState();
             }, true);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Generator/TimeTags/Ja/JaTimeTagGenerator.cs b/osu.Game.Rulesets.Karaoke/Edit/Generator/TimeTags/Ja/JaTimeTagGenerator.cs
index 56ef04997..c9eac85c2 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Generator/TimeTags/Ja/JaTimeTagGenerator.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Generator/TimeTags/Ja/JaTimeTagGenerator.cs
@@ -34,7 +34,7 @@ protected override void TimeTagLogic(Lyric lyric, List<TimeTag> timeTags)
 
                 // add new time tags created from ruby
                 var rubyTags = generateTimeTagByText(ruby.Text);
-                var shiftingTimeTags = rubyTags.Select((x, v) => new TimeTag(new TextIndex(ruby.StartIndex, x.Index.State), x.Time));
+                var shiftingTimeTags = rubyTags.Select((x, _) => new TimeTag(new TextIndex(ruby.StartIndex, x.Index.State), x.Time));
                 timeTags.AddRange(shiftingTimeTags);
             }
         }
diff --git a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/AssignLanguage/AssignLanguageSubScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/AssignLanguage/AssignLanguageSubScreen.cs
index 6f4fba8c2..7e938f150 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/AssignLanguage/AssignLanguageSubScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/AssignLanguage/AssignLanguageSubScreen.cs
@@ -36,7 +36,7 @@ protected override TopNavigation CreateNavigation()
             => new AssignLanguageNavigation(this);
 
         protected override Drawable CreateContent()
-            => base.CreateContent().With(x =>
+            => base.CreateContent().With(_ =>
             {
                 LyricEditor.Mode = LyricEditorMode.Language;
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/DragFile/DragFileSubScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/DragFile/DragFileSubScreen.cs
index 10ae4fadc..e3bc3114d 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/DragFile/DragFileSubScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/DragFile/DragFileSubScreen.cs
@@ -174,7 +174,7 @@ private PopupDialog createUnknownExceptionDialog()
             };
 
         private PopupDialog createCompleteDialog()
-            => new OkPopupDialog(ok => { Complete(); })
+            => new OkPopupDialog(_ => { Complete(); })
             {
                 Icon = FontAwesome.Regular.CheckCircle,
                 HeaderText = @"Import success",
diff --git a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/EditLyric/EditLyricSubScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/EditLyric/EditLyricSubScreen.cs
index cc54979ec..42859e0cc 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/EditLyric/EditLyricSubScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/EditLyric/EditLyricSubScreen.cs
@@ -22,7 +22,7 @@ protected override TopNavigation CreateNavigation()
             => new EditLyricNavigation(this);
 
         protected override Drawable CreateContent()
-            => base.CreateContent().With(x =>
+            => base.CreateContent().With(_ =>
             {
                 LyricEditor.Mode = LyricEditorMode.Manage;
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateRubyRomaji/GenerateRubyRomajiSubScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateRubyRomaji/GenerateRubyRomajiSubScreen.cs
index 2e3908eaa..02fa4811b 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateRubyRomaji/GenerateRubyRomajiSubScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateRubyRomaji/GenerateRubyRomajiSubScreen.cs
@@ -32,7 +32,7 @@ protected override TopNavigation CreateNavigation()
             => new GenerateRubyNavigation(this);
 
         protected override Drawable CreateContent()
-            => base.CreateContent().With(x =>
+            => base.CreateContent().With(_ =>
             {
                 LyricEditor.Mode = LyricEditorMode.EditRomaji;
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateTimeTag/GenerateTimeTagSubScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateTimeTag/GenerateTimeTagSubScreen.cs
index d3b9864dc..6bf4b085a 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateTimeTag/GenerateTimeTagSubScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/ImportLyric/GenerateTimeTag/GenerateTimeTagSubScreen.cs
@@ -22,7 +22,7 @@ protected override TopNavigation CreateNavigation()
             => new GenerateTimeTagNavigation(this);
 
         protected override Drawable CreateContent()
-            => base.CreateContent().With(x =>
+            => base.CreateContent().With(_ =>
             {
                 LyricEditor.Mode = LyricEditorMode.CreateTimeTag;
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/KaraokeSelectionHandler.cs b/osu.Game.Rulesets.Karaoke/Edit/KaraokeSelectionHandler.cs
index ebab16ee2..debd063cc 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/KaraokeSelectionHandler.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/KaraokeSelectionHandler.cs
@@ -147,15 +147,15 @@ private void performColumnMovement(Tone lastTone, MoveSelectionEvent<HitObject>
             var delta = centerPosition.Y - lastCenterPosition;
 
             // get delta tone.
-            var deltaTone = new Tone();
             const float trigger_height = ScrollingNotePlayfield.COLUMN_SPACING + DefaultColumnBackground.COLUMN_HEIGHT;
+            var deltaTone = delta switch
+            {
+                > trigger_height => -new Tone { Half = true },
+                < 0 => new Tone { Half = true },
+                _ => default
+            };
 
-            if (delta > trigger_height)
-                deltaTone = -new Tone { Half = true };
-            else if (delta < 0)
-                deltaTone = new Tone { Half = true };
-
-            if (deltaTone == 0)
+            if (deltaTone == default(Tone))
                 return;
 
             foreach (var note in EditorBeatmap.SelectedHitObjects.OfType<Note>())
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/ApplySelectingArea.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/ApplySelectingArea.cs
index bb43295f2..8567b5546 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/ApplySelectingArea.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/ApplySelectingArea.cs
@@ -122,7 +122,7 @@ private void load(OsuColour colours, LyricSelectionState lyricSelectionState)
             // get bindable and update bindable if select or not select all.
             selectedLyrics = lyricSelectionState.SelectedLyrics.GetBoundCopy();
 
-            selectedLyrics.BindCollectionChanged((a, b) =>
+            selectedLyrics.BindCollectionChanged((_, _) =>
             {
                 var selectAny = selectedLyrics.Any();
                 applyButton.Enabled.Value = selectAny;
@@ -172,14 +172,14 @@ private void load(ILyricEditorState state, LyricSelectionState lyricSelectionSta
                 selectedLyrics = lyricSelectionState.SelectedLyrics.GetBoundCopy();
 
                 // should update background if mode changed.
-                mode.BindValueChanged(e =>
+                mode.BindValueChanged(_ =>
                 {
                     background.Colour = colourProvider.Dark2(state.Mode);
                     allSelectedCheckbox.AccentColour = colourProvider.Colour2(state.Mode);
                 }, true);
 
                 // should disable selection if current lyric is disabled.
-                disableSelectingLyrics.BindCollectionChanged((a, b) =>
+                disableSelectingLyrics.BindCollectionChanged((_, _) =>
                 {
                     var disabledLyricNumber = lyricSelectionState.DisableSelectingLyric.Count;
                     var totalLyrics = beatmap.HitObjects.OfType<Lyric>().Count();
@@ -190,7 +190,7 @@ private void load(ILyricEditorState state, LyricSelectionState lyricSelectionSta
                 });
 
                 // get bindable and update bindable if select or not select all.
-                selectedLyrics.BindCollectionChanged((a, b) =>
+                selectedLyrics.BindCollectionChanged((_, _) =>
                 {
                     if (checkboxClicking)
                         return;
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/DrawableLyricEditListItem.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/DrawableLyricEditListItem.cs
index 83d0f7657..055007f48 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/DrawableLyricEditListItem.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/DrawableLyricEditListItem.cs
@@ -45,7 +45,7 @@ public DrawableLyricEditListItem(Lyric item)
                 removeExtend();
             }, true);
 
-            bindableHoverCaretPosition.BindValueChanged(e =>
+            bindableHoverCaretPosition.BindValueChanged(_ =>
             {
                 updateBackgroundColour();
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageAutoGenerateSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageAutoGenerateSection.cs
index 9f52b03c4..3e22b7c9b 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageAutoGenerateSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageAutoGenerateSection.cs
@@ -16,7 +16,7 @@ public class LanguageAutoGenerateSection : AutoGenerateSection
 
         protected override Dictionary<Lyric, string> GetDisableSelectingLyrics(Lyric[] lyrics)
             => lyrics.Where(x => string.IsNullOrEmpty(x.Text))
-                     .ToDictionary(k => k, i => "Should have text in lyric.");
+                     .ToDictionary(k => k, _ => "Should have text in lyric.");
 
         protected override void Apply(Lyric[] lyrics)
             => lyricManager.AutoDetectLyricLanguage(lyrics);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageMissingSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageMissingSection.cs
index 24292b939..27b25ffbb 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageMissingSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Languages/LanguageMissingSection.cs
@@ -38,7 +38,7 @@ private void load(LyricCheckerManager lyricCheckerManager)
             };
 
             bindableReports = lyricCheckerManager.BindableReports.GetBoundCopy();
-            bindableReports.BindCollectionChanged((a, b) =>
+            bindableReports.BindCollectionChanged((_, _) =>
             {
                 var issues = bindableReports.Values.SelectMany(x => x);
                 table.Issues = issues.Where(x => x.Template is CheckInvalidPropertyLyrics.IssueTemplateNotFillLanguage);
@@ -60,13 +60,13 @@ public IEnumerable<Issue> Issues
                     if (value == null)
                         return;
 
-                    Content = value.Select((g, i) =>
+                    Content = value.Select((g, _) =>
                     {
                         var lyric = g.HitObjects.FirstOrDefault() as Lyric;
                         return createContent(lyric);
                     }).ToArray().ToRectangular();
 
-                    BackgroundFlow.Children = value.Select((g, i) =>
+                    BackgroundFlow.Children = value.Select((g, _) =>
                     {
                         var lyric = g.HitObjects.FirstOrDefault() as Lyric;
                         return new LyricLanguageRowBackground(lyric);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Notes/NoteAutoGenerateSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Notes/NoteAutoGenerateSection.cs
index bdce0b2a8..64a431f93 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Notes/NoteAutoGenerateSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Notes/NoteAutoGenerateSection.cs
@@ -27,7 +27,7 @@ public class NoteAutoGenerateSection : AutoGenerateSection
 
         protected override Dictionary<Lyric, string> GetDisableSelectingLyrics(Lyric[] lyrics)
             => lyricCheckerManager.BindableReports.Where(x => x.Value.OfType<TimeTagIssue>().Any())
-                                  .ToDictionary(k => k.Key, i => "Before generate time-tag, need to assign language first.");
+                                  .ToDictionary(k => k.Key, _ => "Before generate time-tag, need to assign language first.");
 
         protected override void Apply(Lyric[] lyrics)
             => noteManager.AutoGenerateNotes(lyrics);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/Components/LabelledTextTagTextBox.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/Components/LabelledTextTagTextBox.cs
index 42d7d8619..bbe01ae2c 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/Components/LabelledTextTagTextBox.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/Components/LabelledTextTagTextBox.cs
@@ -37,13 +37,13 @@ protected LabelledTextTagTextBox(T textTag)
             Component.Text = textTag.Text;
 
             // should change preview text box if selected ruby/romaji changed.
-            OnCommit += (sender, newText) =>
+            OnCommit += (sender, _) =>
             {
                 textTag.Text = sender.Text;
             };
 
             // change style if focus.
-            SelectedTextTag.BindCollectionChanged((e, a) =>
+            SelectedTextTag.BindCollectionChanged((_, _) =>
             {
                 var highLight = SelectedTextTag.Contains(textTag);
 
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagAutoGenerateSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagAutoGenerateSection.cs
index 05cfc6663..78c1e4998 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagAutoGenerateSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagAutoGenerateSection.cs
@@ -16,7 +16,7 @@ public class RomajiTagAutoGenerateSection : TextTagAutoGenerateSection
 
         protected override Dictionary<Lyric, string> GetDisableSelectingLyrics(Lyric[] lyrics)
             => lyrics.Where(x => x.Language == null)
-                     .ToDictionary(k => k, i => "Before generate romaji-tag, need to assign language first.");
+                     .ToDictionary(k => k, _ => "Before generate romaji-tag, need to assign language first.");
 
         protected override void Apply(Lyric[] lyrics)
             => rubyRomaji.AutoGenerateLyricRomaji(lyrics);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagIssueSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagIssueSection.cs
index 068f610b8..2f271bed6 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagIssueSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RomajiTagIssueSection.cs
@@ -32,7 +32,7 @@ private void load(LyricCheckerManager lyricCheckerManager)
             };
 
             bindableReports = lyricCheckerManager.BindableReports.GetBoundCopy();
-            bindableReports.BindCollectionChanged((a, b) =>
+            bindableReports.BindCollectionChanged((_, _) =>
             {
                 var issues = bindableReports.Values.SelectMany(x => x);
                 table.Issues = issues.OfType<RomajiTagIssue>();
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagAutoGenerateSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagAutoGenerateSection.cs
index f8445dded..687d3330b 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagAutoGenerateSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagAutoGenerateSection.cs
@@ -16,7 +16,7 @@ public class RubyTagAutoGenerateSection : TextTagAutoGenerateSection
 
         protected override Dictionary<Lyric, string> GetDisableSelectingLyrics(Lyric[] lyrics)
             => lyrics.Where(x => x.Language == null)
-                     .ToDictionary(k => k, i => "Before generate ruby-tag, need to assign language first.");
+                     .ToDictionary(k => k, _ => "Before generate ruby-tag, need to assign language first.");
 
         protected override void Apply(Lyric[] lyrics)
             => rubyRomaji.AutoGenerateLyricRuby(lyrics);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagIssueSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagIssueSection.cs
index 8276911f3..075fe8207 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagIssueSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/RubyRomaji/RubyTagIssueSection.cs
@@ -32,7 +32,7 @@ private void load(LyricCheckerManager lyricCheckerManager)
             };
 
             bindableReports = lyricCheckerManager.BindableReports.GetBoundCopy();
-            bindableReports.BindCollectionChanged((a, b) =>
+            bindableReports.BindCollectionChanged((_, _) =>
             {
                 var issues = bindableReports.Values.SelectMany(x => x);
                 table.Issues = issues.OfType<RubyTagIssue>();
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Singers/SingerEditSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Singers/SingerEditSection.cs
index 18cf99444..7e312c2f8 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Singers/SingerEditSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/Singers/SingerEditSection.cs
@@ -24,7 +24,7 @@ public class SingerEditSection : Section
 
         public SingerEditSection()
         {
-            singerIndexes.BindValueChanged(e =>
+            singerIndexes.BindValueChanged(_ =>
             {
                 foreach (var singerLabel in Content.OfType<LabelledSingerSwitchButton>())
                 {
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagAutoGenerateSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagAutoGenerateSection.cs
index d5496b929..4d7d03a81 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagAutoGenerateSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagAutoGenerateSection.cs
@@ -16,7 +16,7 @@ public class TimeTagAutoGenerateSection : AutoGenerateSection
 
         protected override Dictionary<Lyric, string> GetDisableSelectingLyrics(Lyric[] lyrics)
             => lyrics.Where(x => x.Language == null)
-                     .ToDictionary(k => k, i => "Before generate time-tag, need to assign language first.");
+                     .ToDictionary(k => k, _ => "Before generate time-tag, need to assign language first.");
 
         protected override void Apply(Lyric[] lyrics)
             => lyricManager.AutoGenerateTimeTags(lyrics);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagIssueSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagIssueSection.cs
index 4ee5e4aa4..16eb96875 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagIssueSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Extends/TimeTags/TimeTagIssueSection.cs
@@ -45,7 +45,7 @@ private void load(LyricCheckerManager lyricCheckerManager)
             };
 
             bindableReports = lyricCheckerManager.BindableReports.GetBoundCopy();
-            bindableReports.BindCollectionChanged((a, b) =>
+            bindableReports.BindCollectionChanged((_, _) =>
             {
                 // todo : might have filter in here.
                 var issues = bindableReports.Values.SelectMany(x => x);
@@ -68,7 +68,7 @@ public IEnumerable<TimeTagIssue> Issues
                     if (value == null)
                         return;
 
-                    Content = value.Select((g, i) =>
+                    Content = value.Select((g, _) =>
                     {
                         var lyric = g.HitObjects.FirstOrDefault() as Lyric;
 
@@ -88,7 +88,7 @@ public IEnumerable<TimeTagIssue> Issues
                         return rows;
                     }).SelectMany(x => x).ToArray().ToRectangular();
 
-                    BackgroundFlow.Children = value.Select((g, i) =>
+                    BackgroundFlow.Children = value.Select((g, _) =>
                     {
                         var lyric = g.HitObjects.FirstOrDefault() as Lyric;
 
@@ -217,7 +217,7 @@ private void load(ILyricEditorState state, LyricCaretState lyricCaretState, Blue
                 {
                     // update selected state by bindable.
                     selectedTimeTags = blueprintSelectionState.SelectedTimeTags.GetBoundCopy();
-                    selectedTimeTags.BindCollectionChanged((a, b) =>
+                    selectedTimeTags.BindCollectionChanged((_, _) =>
                     {
                         var selected = selectedTimeTags.Contains(timeTag);
                         UpdateState(selected);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/LyricEditor.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/LyricEditor.cs
index adcbee53d..c8cef18c0 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/LyricEditor.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/LyricEditor.cs
@@ -142,21 +142,21 @@ public LyricEditor()
                 skin.FontSize = e.NewValue;
             });
 
-            bindableCreateMovingCaretMode.BindValueChanged(e =>
+            bindableCreateMovingCaretMode.BindValueChanged(_ =>
             {
                 initialCaretPositionAlgorithm();
 
                 lyricCaretState.ResetPosition(Mode);
             });
 
-            bindableRecordingMovingCaretMode.BindValueChanged(e =>
+            bindableRecordingMovingCaretMode.BindValueChanged(_ =>
             {
                 initialCaretPositionAlgorithm();
 
                 lyricCaretState.ResetPosition(Mode);
             });
 
-            lyricSelectionState.Selecting.BindValueChanged(e =>
+            lyricSelectionState.Selecting.BindValueChanged(_ =>
             {
                 initializeApplySelectingArea();
             }, true);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RomajiTagSelectionBlueprint.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RomajiTagSelectionBlueprint.cs
index a6e8e5a3b..541b766c1 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RomajiTagSelectionBlueprint.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RomajiTagSelectionBlueprint.cs
@@ -31,9 +31,9 @@ public RomajiTagSelectionBlueprint(RomajiTag item)
         private void load()
         {
             UpdatePositionAndSize();
-            text.BindValueChanged(e => UpdatePositionAndSize());
-            startIndex.BindValueChanged(e => UpdatePositionAndSize());
-            endIndex.BindValueChanged(e => UpdatePositionAndSize());
+            text.BindValueChanged(_ => UpdatePositionAndSize());
+            startIndex.BindValueChanged(_ => UpdatePositionAndSize());
+            endIndex.BindValueChanged(_ => UpdatePositionAndSize());
         }
     }
 }
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RubyTagSelectionBlueprint.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RubyTagSelectionBlueprint.cs
index 0d005d612..fde38c8f4 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RubyTagSelectionBlueprint.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Blueprints/RubyTagSelectionBlueprint.cs
@@ -31,9 +31,9 @@ public RubyTagSelectionBlueprint(RubyTag item)
         private void load()
         {
             UpdatePositionAndSize();
-            text.BindValueChanged(e => UpdatePositionAndSize());
-            startIndex.BindValueChanged(e => UpdatePositionAndSize());
-            endIndex.BindValueChanged(e => UpdatePositionAndSize());
+            text.BindValueChanged(_ => UpdatePositionAndSize());
+            startIndex.BindValueChanged(_ => UpdatePositionAndSize());
+            endIndex.BindValueChanged(_ => UpdatePositionAndSize());
         }
     }
 }
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/EditorLyricPiece.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/EditorLyricPiece.cs
index bcde89539..be8f2ab5d 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/EditorLyricPiece.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/EditorLyricPiece.cs
@@ -192,7 +192,7 @@ public Vector2 GetTimeTagPosition(TextIndex index)
             }
 
             private int skinIndex(PositionText[] positionTexts, int endIndex)
-                => positionTexts.Where((x, i) => i < endIndex).Sum(x => x.Text.Length);
+                => positionTexts.Where((_, i) => i < endIndex).Sum(x => x.Text.Length);
 
             private bool propertyMatched(PositionText positionText, ITextTag textTag)
                 => positionText.StartIndex == textTag.StartIndex && positionText.EndIndex == textTag.EndIndex && positionText.Text == textTag.Text;
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/FixedInfo/InvalidInfo.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/FixedInfo/InvalidInfo.cs
index 4c6f6d28f..f90f7159d 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/FixedInfo/InvalidInfo.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/FixedInfo/InvalidInfo.cs
@@ -36,7 +36,7 @@ public InvalidInfo(Lyric lyric)
         [BackgroundDependencyLoader]
         private void load(OsuColour colours, LyricCheckerManager lyricCheckerManager)
         {
-            lyricCheckerManager.BindableReports.BindCollectionChanged((i, args) =>
+            lyricCheckerManager.BindableReports.BindCollectionChanged((_, args) =>
             {
                 // Ignore remove case
                 if (args.NewItems == null)
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Parts/DrawableTimeTag.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Parts/DrawableTimeTag.cs
index b4c9ad297..3a2ea3097 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Parts/DrawableTimeTag.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/Parts/DrawableTimeTag.cs
@@ -57,13 +57,13 @@ private void load(OsuColour colours, ILyricEditorState state, KaraokeRulesetLyri
             bindableMode = state.BindableMode.GetBoundCopy();
             bindableRecordingMovingCaretMode = lyricEditorConfigManager.GetBindable<MovingTimeTagCaretMode>(KaraokeRulesetLyricEditorSetting.RecordingTimeTagMovingCaretMode).GetBoundCopy();
 
-            bindableMode.BindValueChanged(x =>
+            bindableMode.BindValueChanged(_ =>
             {
                 // should wait until caret position algorithm loaded.
                 Schedule(updateStyle);
             });
 
-            bindableRecordingMovingCaretMode.BindValueChanged(x =>
+            bindableRecordingMovingCaretMode.BindValueChanged(_ =>
             {
                 // should wait until caret position algorithm loaded.
                 Schedule(updateStyle);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/SubInfo/TimeTagInfo.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/SubInfo/TimeTagInfo.cs
index f08243203..d017989f0 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/SubInfo/TimeTagInfo.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Components/SubInfo/TimeTagInfo.cs
@@ -13,7 +13,7 @@ public class TimeTagInfo : SubInfo
         public TimeTagInfo(Lyric lyric)
             : base(lyric)
         {
-            lyric.TimeTagsBindable.BindValueChanged(value =>
+            lyric.TimeTagsBindable.BindValueChanged(_ =>
             {
                 BadgeText = LyricUtils.TimeTagTimeFormattedString(Lyric);
             }, true);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/EditLyricRow.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/EditLyricRow.cs
index b1139a4dc..2cb7d44b3 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/EditLyricRow.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/EditLyricRow.cs
@@ -328,7 +328,7 @@ public SingleLyricEditor(Lyric lyric)
                     }
                 };
 
-                lyricPiece.TimeTagsBindable.BindValueChanged(e =>
+                lyricPiece.TimeTagsBindable.BindValueChanged(_ =>
                 {
                     ScheduleAfterChildren(UpdateTimeTags);
                 }, true);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/Components/TimeTagZoomableScrollContainer.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/Components/TimeTagZoomableScrollContainer.cs
index 985e12f07..539889a49 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/Components/TimeTagZoomableScrollContainer.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/Components/TimeTagZoomableScrollContainer.cs
@@ -43,7 +43,7 @@ protected TimeTagZoomableScrollContainer(Lyric lyric)
             {
                 foreach (var obj in addItems)
                 {
-                    obj.TimeBindable.BindValueChanged(e =>
+                    obj.TimeBindable.BindValueChanged(_ =>
                     {
                         updateTimeRange();
                     });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/TimeTags/TimeTagEditorHitObjectBlueprint.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/TimeTags/TimeTagEditorHitObjectBlueprint.cs
index e0cb74958..a4e5d7a8b 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/TimeTags/TimeTagEditorHitObjectBlueprint.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/Extends/TimeTags/TimeTagEditorHitObjectBlueprint.cs
@@ -87,7 +87,7 @@ private void load(TimeTagEditor timeline, OsuColour colours)
             timeTagText.Text = LyricUtils.GetTimeTagDisplayRubyText(timeline.HitObject, Item);
             timeTagPiece.Colour = colours.BlueLight;
             timeTagWithNoTimePiece.Colour = colours.Red;
-            startTime.BindValueChanged(e =>
+            startTime.BindValueChanged(_ =>
             {
                 var hasValue = hasTime();
 
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/LyricEditorRow.cs b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/LyricEditorRow.cs
index d7a4729f5..2e85adf9d 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/LyricEditorRow.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Lyrics/Rows/LyricEditorRow.cs
@@ -106,7 +106,7 @@ private void load(ILyricEditorState state, LyricSelectionState lyricSelectionSta
                 selectedLyrics = lyricSelectionState.SelectedLyrics.GetBoundCopy();
 
                 // should update background if mode changed.
-                mode.BindValueChanged(e =>
+                mode.BindValueChanged(_ =>
                 {
                     background.Colour = colourProvider.Dark2(state.Mode);
                     selectedCheckbox.AccentColour = colourProvider.Colour2(state.Mode);
@@ -126,7 +126,7 @@ private void load(ILyricEditorState state, LyricSelectionState lyricSelectionSta
                 }, true);
 
                 // get bindable and update bindable if check / uncheck.
-                selectedLyrics.BindCollectionChanged((a, b) =>
+                selectedLyrics.BindCollectionChanged((_, _) =>
                 {
                     if (selectedCheckbox.Current.Disabled)
                         return;
@@ -136,7 +136,7 @@ private void load(ILyricEditorState state, LyricSelectionState lyricSelectionSta
                 }, true);
 
                 // should disable selection if current lyric is disabled.
-                disableSelectingLyrics.BindCollectionChanged((a, b) =>
+                disableSelectingLyrics.BindCollectionChanged((_, _) =>
                 {
                     var disabled = disableSelectingLyrics.Keys.Contains(lyric);
                     selectedCheckbox.Current.Disabled = disabled;
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/Components/Blueprints/SingerLyricEditorHitObjectBlueprint.cs b/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/Components/Blueprints/SingerLyricEditorHitObjectBlueprint.cs
index bed4f84dd..f80c9a725 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/Components/Blueprints/SingerLyricEditorHitObjectBlueprint.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/Components/Blueprints/SingerLyricEditorHitObjectBlueprint.cs
@@ -71,7 +71,7 @@ public LyricTimelineHitObjectBlueprint(Lyric item)
         [BackgroundDependencyLoader]
         private void load(LyricManager lyricManager, SingerLyricEditor editor)
         {
-            singersBindable.BindValueChanged(e =>
+            singersBindable.BindValueChanged(_ =>
             {
                 // Check is lyric contains this singer, or default singer
                 isSingerMatched = lyricInCurrentSinger(Item, editor.Singer);
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/SingerLyricPlacementRow.cs b/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/SingerLyricPlacementRow.cs
index ba030377d..a053656c9 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/SingerLyricPlacementRow.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Singers/Rows/SingerLyricPlacementRow.cs
@@ -122,7 +122,7 @@ public DrawableSingerInfo(Singer singer)
                     updateSingerInfo(e.NewValue);
                 }, true);
 
-                singer.OrderBindable.BindValueChanged(x =>
+                singer.OrderBindable.BindValueChanged(_ =>
                 {
                     updateSingerName(singer);
                 });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Singers/SingerManager.cs b/osu.Game.Rulesets.Karaoke/Edit/Singers/SingerManager.cs
index 5ac20ad34..3779338f0 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Singers/SingerManager.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Singers/SingerManager.cs
@@ -37,7 +37,7 @@ private void load()
             Singers.AddRange(karaokeBeatmap.Singers);
 
             // should write-back if singer changed.
-            Singers.BindCollectionChanged((a, b) =>
+            Singers.BindCollectionChanged((_, _) =>
             {
                 karaokeBeatmap.Singers = Singers.ToArray();
             });
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateEditSection.cs b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateEditSection.cs
index cdfde5976..0f920dd0c 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateEditSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateEditSection.cs
@@ -215,7 +215,7 @@ private void load(TranslateManager translateManager, OsuColour colours)
             timeSectionBackground.Colour = colours.ContextMenuGray;
             lyricSectionBackground.Colour = colours.Gray9;
 
-            translateGrid.RowDimensions = translateManager.Lyrics.Select(x => new Dimension(GridSizeMode.Absolute, row_height)).ToArray();
+            translateGrid.RowDimensions = translateManager.Lyrics.Select(_ => new Dimension(GridSizeMode.Absolute, row_height)).ToArray();
             translateGrid.Content = createContent(languageDropdown.Current);
         }
 
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateManager.cs b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateManager.cs
index 85ac6fc99..492e8645c 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateManager.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateManager.cs
@@ -36,7 +36,7 @@ private void load()
                 return;
 
             Languages.AddRange(karaokeBeatmap.AvailableTranslates);
-            Languages.BindCollectionChanged((a, b) => { karaokeBeatmap.AvailableTranslates = Languages.ToArray(); });
+            Languages.BindCollectionChanged((_, _) => { karaokeBeatmap.AvailableTranslates = Languages.ToArray(); });
         }
 
         public void AddLanguage(CultureInfo cultureInfo)
diff --git a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateScreen.cs b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateScreen.cs
index f9d34f855..395424558 100644
--- a/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Edit/Translate/TranslateScreen.cs
@@ -65,7 +65,7 @@ private void load(OsuColour colours, DialogOverlay dialogOverlay, LanguageSelect
 
             // ask only once if contains no language after switch to translate editor.
             bool alreadyAsked;
-            TranslateManager.Languages.BindCollectionChanged((a, b) =>
+            TranslateManager.Languages.BindCollectionChanged((_, _) =>
             {
                 alreadyAsked = true;
 
diff --git a/osu.Game.Rulesets.Karaoke/Graphics/UserInterface/FontSelectionDialog.cs b/osu.Game.Rulesets.Karaoke/Graphics/UserInterface/FontSelectionDialog.cs
index fdedc6a60..c47648c35 100644
--- a/osu.Game.Rulesets.Karaoke/Graphics/UserInterface/FontSelectionDialog.cs
+++ b/osu.Game.Rulesets.Karaoke/Graphics/UserInterface/FontSelectionDialog.cs
@@ -176,7 +176,7 @@ public FontSelectionDialog()
                 }
             };
 
-            fonts.BindCollectionChanged((a, b) =>
+            fonts.BindCollectionChanged((_, b) =>
             {
                 // re-calculate if source changed.
                 Schedule(() =>
@@ -217,9 +217,9 @@ public FontSelectionDialog()
                 // set to first or empty if change new family.
                 weightProperty.Current.Value = weight.FirstOrDefault();
             });
-            weightProperty.Current.BindValueChanged(x => previewChange());
-            fontSizeProperty.Current.BindValueChanged(x => previewChange());
-            fixedWidthCheckbox.Current.BindValueChanged(x => previewChange());
+            weightProperty.Current.BindValueChanged(_ => previewChange());
+            fontSizeProperty.Current.BindValueChanged(_ => previewChange());
+            fixedWidthCheckbox.Current.BindValueChanged(_ => previewChange());
             Current.BindValueChanged(e =>
             {
                 var newFont = e.NewValue;
diff --git a/osu.Game.Rulesets.Karaoke/IO/Serialization/Converters/FontUsageConvertor.cs b/osu.Game.Rulesets.Karaoke/IO/Serialization/Converters/FontUsageConvertor.cs
index 28c6476b9..a65761eef 100644
--- a/osu.Game.Rulesets.Karaoke/IO/Serialization/Converters/FontUsageConvertor.cs
+++ b/osu.Game.Rulesets.Karaoke/IO/Serialization/Converters/FontUsageConvertor.cs
@@ -23,20 +23,15 @@ public override FontUsage ReadJson(JsonReader reader, Type objectType, FontUsage
 
             var font = new FontUsage(size: default_text_size);
 
-            foreach (var property in properties)
+            return properties.Aggregate(font, (current, property) => property.Name switch
             {
-                font = property.Name switch
-                {
-                    "family" => font.With(property.Value.ToObject<string>()),
-                    "weight" => font.With(weight: property.Value.ToObject<string>()),
-                    "size" => font.With(size: property.Value.ToObject<float>()),
-                    "italics" => font.With(italics: property.Value.ToObject<bool>()),
-                    "fixedWidth" => font.With(fixedWidth: property.Value.ToObject<bool>()),
-                    _ => font
-                };
-            }
-
-            return font;
+                "family" => current.With(property.Value.ToObject<string>()),
+                "weight" => current.With(weight: property.Value.ToObject<string>()),
+                "size" => current.With(size: property.Value.ToObject<float>()),
+                "italics" => current.With(italics: property.Value.ToObject<bool>()),
+                "fixedWidth" => current.With(fixedWidth: property.Value.ToObject<bool>()),
+                _ => current
+            });
         }
 
         public override void WriteJson(JsonWriter writer, FontUsage value, JsonSerializer serializer)
diff --git a/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableLyric.cs b/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableLyric.cs
index d865a8e53..7da49eb2c 100644
--- a/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableLyric.cs
+++ b/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableLyric.cs
@@ -80,8 +80,8 @@ private void load([CanBeNull] KaraokeSessionStatics session)
                 Origin = Anchor.TopLeft,
             });
 
-            useTranslateBindable.BindValueChanged(e => applyTranslate());
-            preferLanguageBindable.BindValueChanged(e => applyTranslate());
+            useTranslateBindable.BindValueChanged(_ => applyTranslate());
+            preferLanguageBindable.BindValueChanged(_ => applyTranslate());
             displayRubyBindable.BindValueChanged(e => lyricPieces.ForEach(x => x.DisplayRuby = e.NewValue));
             displayRomajiBindable.BindValueChanged(e => lyricPieces.ForEach(x => x.DisplayRomaji = e.NewValue));
 
@@ -102,9 +102,9 @@ private void load([CanBeNull] KaraokeSessionStatics session)
                 config.BindWith(KaraokeRulesetSetting.DisplayRomaji, displayRomajiBindable);
             }
 
-            singersBindable.BindValueChanged(index => { updateFontStyle(); });
-            layoutIndexBindable.BindValueChanged(index => { updateLayout(); });
-            translateTextBindable.BindCollectionChanged((_, args) => { applyTranslate(); });
+            singersBindable.BindValueChanged(_ => { updateFontStyle(); });
+            layoutIndexBindable.BindValueChanged(_ => { updateLayout(); });
+            translateTextBindable.BindCollectionChanged((_, _) => { applyTranslate(); });
 
             if (config != null)
             {
@@ -114,10 +114,10 @@ private void load([CanBeNull] KaraokeSessionStatics session)
                 config.BindWith(KaraokeRulesetSetting.TranslateFont, translateFontUsageBindable);
             }
 
-            mainFontUsageBindable.BindValueChanged(e => updateFontUsage());
-            rubyFontUsageBindable.BindValueChanged(e => updateFontUsage());
-            romajiFontUsageBindable.BindValueChanged(e => updateFontUsage());
-            translateFontUsageBindable.BindValueChanged(e => updateFontUsage());
+            mainFontUsageBindable.BindValueChanged(_ => updateFontUsage());
+            rubyFontUsageBindable.BindValueChanged(_ => updateFontUsage());
+            romajiFontUsageBindable.BindValueChanged(_ => updateFontUsage());
+            translateFontUsageBindable.BindValueChanged(_ => updateFontUsage());
         }
 
         protected override void OnApply()
diff --git a/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableNote.cs b/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableNote.cs
index b05a49254..ea5d4956d 100644
--- a/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableNote.cs
+++ b/osu.Game.Rulesets.Karaoke/Objects/Drawables/DrawableNote.cs
@@ -71,12 +71,12 @@ private void load(INotePositionInfo notePositionInfo)
         {
             positionBindable.BindTo(notePositionInfo.Position);
 
-            positionBindable.BindValueChanged(e => updateNotePositionAndHeight());
+            positionBindable.BindValueChanged(_ => updateNotePositionAndHeight());
             TextBindable.BindValueChanged(_ => { changeText(HitObject); });
             AlternativeTextBindable.BindValueChanged(_ => { changeText(HitObject); });
-            SingersBindable.BindValueChanged(index => { ApplySkin(CurrentSkin, false); });
+            SingersBindable.BindValueChanged(_ => { ApplySkin(CurrentSkin, false); });
             DisplayBindable.BindValueChanged(e => { (Result.Judgement as KaraokeNoteJudgement).Saitenable = e.NewValue; });
-            ToneBindable.BindValueChanged(e => updateNotePositionAndHeight());
+            ToneBindable.BindValueChanged(_ => updateNotePositionAndHeight());
 
             void updateNotePositionAndHeight()
             {
diff --git a/osu.Game.Rulesets.Karaoke/Overlays/Changelog/Sidebar/ChangelogSection.cs b/osu.Game.Rulesets.Karaoke/Overlays/Changelog/Sidebar/ChangelogSection.cs
index 1bc969282..6020446e8 100644
--- a/osu.Game.Rulesets.Karaoke/Overlays/Changelog/Sidebar/ChangelogSection.cs
+++ b/osu.Game.Rulesets.Karaoke/Overlays/Changelog/Sidebar/ChangelogSection.cs
@@ -1,6 +1,7 @@
 // Copyright (c) andy840119 <andy840119@gmail.com>. Licensed under the GPL Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
@@ -28,7 +29,13 @@ public class ChangelogSection : CompositeDrawable
 
         public ChangelogSection(int year, IEnumerable<APIChangelogBuild> posts)
         {
-            Debug.Assert(posts.All(p => p.PublishedAt.Year == year));
+            Debug.Assert(posts.All(p =>
+            {
+                if (p == null)
+                    throw new ArgumentNullException(nameof(p));
+
+                return p.PublishedAt.Year == year;
+            }));
 
             RelativeSizeAxes = Axes.X;
             AutoSizeAxes = Axes.Y;
diff --git a/osu.Game.Rulesets.Karaoke/Replays/KaraokeAutoGeneratorBySinger.cs b/osu.Game.Rulesets.Karaoke/Replays/KaraokeAutoGeneratorBySinger.cs
index bda7182b8..e4624ca8e 100644
--- a/osu.Game.Rulesets.Karaoke/Replays/KaraokeAutoGeneratorBySinger.cs
+++ b/osu.Game.Rulesets.Karaoke/Replays/KaraokeAutoGeneratorBySinger.cs
@@ -62,7 +62,7 @@ public KaraokeAutoGeneratorBySinger(KaraokeBeatmap beatmap, Stream data)
                     lengthSum += length;
 
                     // usually sample 1 is vocal
-                    var channel0Sample = sampleBuffer.Where((x, i) => i % 2 == 0).ToArray();
+                    var channel0Sample = sampleBuffer.Where((_, i) => i % 2 == 0).ToArray();
                     //var channel1Sample = sampleBuffer.Where((x, i) => i % 2 != 0).ToArray();
 
                     // Convert buffer to pitch data
diff --git a/osu.Game.Rulesets.Karaoke/Screens/Config/KaraokeConfigScreen.cs b/osu.Game.Rulesets.Karaoke/Screens/Config/KaraokeConfigScreen.cs
index 0741a4187..857d8358e 100644
--- a/osu.Game.Rulesets.Karaoke/Screens/Config/KaraokeConfigScreen.cs
+++ b/osu.Game.Rulesets.Karaoke/Screens/Config/KaraokeConfigScreen.cs
@@ -103,13 +103,13 @@ protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnl
         private void load(GameHost host)
         {
             // todo : not really sure how to clean-up cached manager
-            if (host.Dependencies.Get<FontManager>() == null)
-            {
-                // because not possible to remove cache from host, so only inject once.
-                var manager = new FontManager();
-                AddInternal(manager);
-                host.Dependencies.Cache(manager);
-            }
+            if (host.Dependencies.Get<FontManager>() != null)
+                return;
+
+            // because not possible to remove cache from host, so only inject once.
+            var manager = new FontManager();
+            AddInternal(manager);
+            host.Dependencies.Cache(manager);
         }
 
         protected override void LoadComplete()
diff --git a/osu.Game.Rulesets.Karaoke/Skinning/Default/DefaultLyricPiece.cs b/osu.Game.Rulesets.Karaoke/Skinning/Default/DefaultLyricPiece.cs
index 384733030..b16925bc3 100644
--- a/osu.Game.Rulesets.Karaoke/Skinning/Default/DefaultLyricPiece.cs
+++ b/osu.Game.Rulesets.Karaoke/Skinning/Default/DefaultLyricPiece.cs
@@ -53,9 +53,9 @@ protected DefaultLyricPiece(Lyric hitObject, int chunkIndex = whole_chunk_index)
             {
                 foreach (var obj in addItems)
                 {
-                    obj.StartIndexBindable.BindValueChanged(x => applyRuby(RubyTagsBindable.Value));
-                    obj.EndIndexBindable.BindValueChanged(x => applyRuby(RubyTagsBindable.Value));
-                    obj.TextBindable.BindValueChanged(x => applyRuby(RubyTagsBindable.Value));
+                    obj.StartIndexBindable.BindValueChanged(_ => applyRuby(RubyTagsBindable.Value));
+                    obj.EndIndexBindable.BindValueChanged(_ => applyRuby(RubyTagsBindable.Value));
+                    obj.TextBindable.BindValueChanged(_ => applyRuby(RubyTagsBindable.Value));
                 }
             }, removedItems =>
             {
@@ -71,9 +71,9 @@ protected DefaultLyricPiece(Lyric hitObject, int chunkIndex = whole_chunk_index)
             {
                 foreach (var obj in addItems)
                 {
-                    obj.StartIndexBindable.BindValueChanged(x => applyRomaji(RomajiTagsBindable.Value));
-                    obj.EndIndexBindable.BindValueChanged(x => applyRomaji(RomajiTagsBindable.Value));
-                    obj.TextBindable.BindValueChanged(x => applyRomaji(RomajiTagsBindable.Value));
+                    obj.StartIndexBindable.BindValueChanged(_ => applyRomaji(RomajiTagsBindable.Value));
+                    obj.EndIndexBindable.BindValueChanged(_ => applyRomaji(RomajiTagsBindable.Value));
+                    obj.TextBindable.BindValueChanged(_ => applyRomaji(RomajiTagsBindable.Value));
                 }
             }, removedItems =>
             {
diff --git a/osu.Game.Rulesets.Karaoke/Skinning/Fonts/FontManager.cs b/osu.Game.Rulesets.Karaoke/Skinning/Fonts/FontManager.cs
index f593a23aa..6dc740807 100644
--- a/osu.Game.Rulesets.Karaoke/Skinning/Fonts/FontManager.cs
+++ b/osu.Game.Rulesets.Karaoke/Skinning/Fonts/FontManager.cs
@@ -187,7 +187,7 @@ public IResourceStore<TextureUpload> GetGlyphStore(FontInfo fontInfo)
             {
                 FontFormat.Fnt => getFntGlyphStore(storage, fontName),
                 FontFormat.Ttf => getTtfGlyphStore(storage, fontName),
-                _ => throw new ArgumentOutOfRangeException(nameof(fontFormat))
+                FontFormat.Internal or _ => throw new ArgumentOutOfRangeException(nameof(fontFormat))
             };
         }
 
@@ -218,9 +218,9 @@ private TtfGlyphStore getTtfGlyphStore(Storage storage, string fontName)
         private static string getPathByFontType(FontFormat type) =>
             type switch
             {
-                FontFormat.Fnt => $"fnt",
-                FontFormat.Ttf => $"ttf",
-                _ => throw new ArgumentOutOfRangeException(nameof(type))
+                FontFormat.Fnt => "fnt",
+                FontFormat.Ttf => "ttf",
+                FontFormat.Internal or _ => throw new ArgumentOutOfRangeException(nameof(type))
             };
 
         private static string getExtensionByFontType(FontFormat type) =>
@@ -228,7 +228,7 @@ private static string getExtensionByFontType(FontFormat type) =>
             {
                 FontFormat.Fnt => "zipfnt",
                 FontFormat.Ttf => "ttf",
-                _ => throw new ArgumentOutOfRangeException(nameof(type))
+                FontFormat.Internal or _ => throw new ArgumentOutOfRangeException(nameof(type))
             };
 
         private static FontFormat getFontTypeByExtension(string extension) =>
diff --git a/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyHitExplosion.cs b/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyHitExplosion.cs
index 18773d97f..b90453476 100644
--- a/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyHitExplosion.cs
+++ b/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyHitExplosion.cs
@@ -36,7 +36,7 @@ private void load(ISkinSource skin, IScrollingInfo scrollingInfo)
             // This animation is discarded and re-queried with the appropriate frame length afterwards.
             var tmp = skin.GetAnimation(imageName, true, false);
             double frameLength = 0;
-            if (tmp is IFramedAnimation tmpAnimation && tmpAnimation.FrameCount > 0)
+            if (tmp is IFramedAnimation { FrameCount: > 0 } tmpAnimation)
                 frameLength = Math.Max(1000 / 60.0, 170.0 / tmpAnimation.FrameCount);
 
             explosion = skin.GetAnimation(imageName, true, false, frameLength: frameLength).With(d =>
diff --git a/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyNotePiece.cs b/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyNotePiece.cs
index 8b9d6dae7..40f995368 100644
--- a/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyNotePiece.cs
+++ b/osu.Game.Rulesets.Karaoke/Skinning/Legacy/LegacyNotePiece.cs
@@ -127,11 +127,11 @@ protected virtual void OnDirectionChanged(ValueChangedEvent<ScrollingDirection>
         {
             if (direction.NewValue == ScrollingDirection.Left)
             {
-                InternalChildren.ForEach(x => Scale = Vector2.One);
+                InternalChildren.ForEach(x => x.Scale = Vector2.One);
             }
             else
             {
-                InternalChildren.ForEach(x => Scale = new Vector2(-1, 1));
+                InternalChildren.ForEach(x => x.Scale = new Vector2(-1, 1));
             }
         }
 
diff --git a/osu.Game.Rulesets.Karaoke/UI/Position/NotePositionInfo.cs b/osu.Game.Rulesets.Karaoke/UI/Position/NotePositionInfo.cs
index ca5159613..8ca41c7ea 100644
--- a/osu.Game.Rulesets.Karaoke/UI/Position/NotePositionInfo.cs
+++ b/osu.Game.Rulesets.Karaoke/UI/Position/NotePositionInfo.cs
@@ -44,8 +44,8 @@ protected override void SkinChanged(ISkinSource skin)
             bindableColumnHeight.BindTo(columnHeight);
             bindableColumnSpacing.BindTo(columnSpacing);
 
-            bindableColumnHeight.BindValueChanged(e => updatePositionCalculator());
-            bindableColumnSpacing.BindValueChanged(e => updatePositionCalculator());
+            bindableColumnHeight.BindValueChanged(_ => updatePositionCalculator());
+            bindableColumnSpacing.BindValueChanged(_ => updatePositionCalculator());
         }
 
         private void updatePositionCalculator()