diff --git a/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs b/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
index bd26a99e51..ba7c6e9d33 100644
--- a/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
+++ b/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
@@ -59,11 +59,6 @@ namespace osu.Game.Rulesets.Osu.Edit
         {
             LayerBelowRuleset.AddRange(new Drawable[]
             {
-                new PlayfieldBorder
-                {
-                    RelativeSizeAxes = Axes.Both,
-                    PlayfieldBorderStyle = { Value = PlayfieldBorderStyle.Corners }
-                },
                 distanceSnapGridContainer = new Container
                 {
                     RelativeSizeAxes = Axes.Both
diff --git a/osu.Game.Tests/Visual/Editing/TestSceneHitObjectComposer.cs b/osu.Game.Tests/Visual/Editing/TestSceneHitObjectComposer.cs
index ae1b691767..c9d44fdab7 100644
--- a/osu.Game.Tests/Visual/Editing/TestSceneHitObjectComposer.cs
+++ b/osu.Game.Tests/Visual/Editing/TestSceneHitObjectComposer.cs
@@ -19,6 +19,7 @@ using osu.Game.Rulesets.Osu.Edit;
 using osu.Game.Rulesets.Osu.Objects;
 using osu.Game.Screens.Edit;
 using osu.Game.Screens.Edit.Components.RadioButtons;
+using osu.Game.Screens.Edit.Components.TernaryButtons;
 using osu.Game.Screens.Edit.Compose.Components;
 using osuTK;
 using osuTK.Input;
@@ -70,6 +71,11 @@ namespace osu.Game.Tests.Visual.Editing
                 Child = editorBeatmapContainer = new EditorBeatmapContainer(Beatmap.Value)
                 {
                     Child = hitObjectComposer = new OsuHitObjectComposer(new OsuRuleset())
+                    {
+                        // force the composer to fully overlap the playfield area by setting a 4:3 aspect ratio.
+                        FillMode = FillMode.Fit,
+                        FillAspectRatio = 4 / 3f
+                    }
                 };
             });
         }
@@ -87,6 +93,65 @@ namespace osu.Game.Tests.Visual.Editing
             AddAssert("Tool changed", () => hitObjectComposer.ChildrenOfType<ComposeBlueprintContainer>().First().CurrentTool is HitCircleCompositionTool);
         }
 
+        [Test]
+        public void TestPlacementFailsWhenClickingButton()
+        {
+            AddStep("clear all control points and hitobjects", () =>
+            {
+                editorBeatmap.ControlPointInfo.Clear();
+                editorBeatmap.Clear();
+            });
+
+            AddStep("Add timing point", () => editorBeatmap.ControlPointInfo.Add(0, new TimingControlPoint()));
+
+            AddStep("Change to hitcircle", () => hitObjectComposer.ChildrenOfType<EditorRadioButton>().First(d => d.Button.Label == "HitCircle").TriggerClick());
+
+            AddStep("move mouse to overlapping toggle button", () =>
+            {
+                var playfield = hitObjectComposer.Playfield.ScreenSpaceDrawQuad;
+                var button = hitObjectComposer
+                             .ChildrenOfType<ExpandingToolboxContainer>().First()
+                             .ChildrenOfType<DrawableTernaryButton>().First(b => playfield.Contains(b.ScreenSpaceDrawQuad.Centre));
+
+                InputManager.MoveMouseTo(button);
+            });
+
+            AddAssert("no circles placed", () => editorBeatmap.HitObjects.Count == 0);
+
+            AddStep("attempt place circle", () => InputManager.Click(MouseButton.Left));
+
+            AddAssert("no circles placed", () => editorBeatmap.HitObjects.Count == 0);
+        }
+
+        [Test]
+        public void TestPlacementWithinToolboxScrollArea()
+        {
+            AddStep("clear all control points and hitobjects", () =>
+            {
+                editorBeatmap.ControlPointInfo.Clear();
+                editorBeatmap.Clear();
+            });
+
+            AddStep("Add timing point", () => editorBeatmap.ControlPointInfo.Add(0, new TimingControlPoint()));
+
+            AddStep("Change to hitcircle", () => hitObjectComposer.ChildrenOfType<EditorRadioButton>().First(d => d.Button.Label == "HitCircle").TriggerClick());
+
+            AddStep("move mouse to scroll area", () =>
+            {
+                // Specifically wanting to test the area of overlap between the left expanding toolbox container
+                // and the playfield/composer.
+                var scrollArea = hitObjectComposer.ChildrenOfType<ExpandingToolboxContainer>().First().ScreenSpaceDrawQuad;
+                var playfield = hitObjectComposer.Playfield.ScreenSpaceDrawQuad;
+                InputManager.MoveMouseTo(new Vector2(scrollArea.TopLeft.X + 1, playfield.Centre.Y));
+            });
+
+            AddAssert("no circles placed", () => editorBeatmap.HitObjects.Count == 0);
+
+            AddStep("place circle", () => InputManager.Click(MouseButton.Left));
+
+            AddAssert("circle placed", () => editorBeatmap.HitObjects.Count == 1);
+        }
+
         [Test]
         public void TestDistanceSpacingHotkeys()
         {
diff --git a/osu.Game.Tests/Visual/UserInterface/TestSceneModSelectScreen.cs b/osu.Game.Tests/Visual/UserInterface/TestSceneModSelectScreen.cs
index ec6e962c6a..bdb423a43c 100644
--- a/osu.Game.Tests/Visual/UserInterface/TestSceneModSelectScreen.cs
+++ b/osu.Game.Tests/Visual/UserInterface/TestSceneModSelectScreen.cs
@@ -2,17 +2,21 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Allocation;
+using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Testing;
 using osu.Framework.Utils;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Overlays.Mods;
+using osu.Game.Overlays.Settings;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Osu;
 using osu.Game.Rulesets.Osu.Mods;
 using osuTK.Input;
 
@@ -64,6 +68,7 @@ namespace osu.Game.Tests.Visual.UserInterface
                 return Precision.AlmostEquals(multiplier, modSelectScreen.ChildrenOfType<DifficultyMultiplierDisplay>().Single().Current.Value);
             });
             assertCustomisationToggleState(disabled: false, active: false);
+            AddAssert("setting items created", () => modSelectScreen.ChildrenOfType<ISettingsItem>().Any());
         }
 
         [Test]
@@ -78,6 +83,7 @@ namespace osu.Game.Tests.Visual.UserInterface
                 return Precision.AlmostEquals(multiplier, modSelectScreen.ChildrenOfType<DifficultyMultiplierDisplay>().Single().Current.Value);
             });
             assertCustomisationToggleState(disabled: false, active: false);
+            AddAssert("setting items created", () => modSelectScreen.ChildrenOfType<ISettingsItem>().Any());
         }
 
         [Test]
@@ -98,17 +104,25 @@ namespace osu.Game.Tests.Visual.UserInterface
 
             AddStep("activate DT", () => getPanelForMod(typeof(OsuModDoubleTime)).TriggerClick());
             AddAssert("DT active", () => SelectedMods.Value.Single().GetType() == typeof(OsuModDoubleTime));
+            AddAssert("DT panel active", () => getPanelForMod(typeof(OsuModDoubleTime)).Active.Value);
 
             AddStep("activate NC", () => getPanelForMod(typeof(OsuModNightcore)).TriggerClick());
             AddAssert("only NC active", () => SelectedMods.Value.Single().GetType() == typeof(OsuModNightcore));
+            AddAssert("DT panel not active", () => !getPanelForMod(typeof(OsuModDoubleTime)).Active.Value);
+            AddAssert("NC panel active", () => getPanelForMod(typeof(OsuModNightcore)).Active.Value);
 
             AddStep("activate HR", () => getPanelForMod(typeof(OsuModHardRock)).TriggerClick());
             AddAssert("NC+HR active", () => SelectedMods.Value.Any(mod => mod.GetType() == typeof(OsuModNightcore))
                                             && SelectedMods.Value.Any(mod => mod.GetType() == typeof(OsuModHardRock)));
+            AddAssert("NC panel active", () => getPanelForMod(typeof(OsuModNightcore)).Active.Value);
+            AddAssert("HR panel active", () => getPanelForMod(typeof(OsuModHardRock)).Active.Value);
 
             AddStep("activate MR", () => getPanelForMod(typeof(OsuModMirror)).TriggerClick());
             AddAssert("NC+MR active", () => SelectedMods.Value.Any(mod => mod.GetType() == typeof(OsuModNightcore))
                                             && SelectedMods.Value.Any(mod => mod.GetType() == typeof(OsuModMirror)));
+            AddAssert("NC panel active", () => getPanelForMod(typeof(OsuModNightcore)).Active.Value);
+            AddAssert("HR panel not active", () => !getPanelForMod(typeof(OsuModHardRock)).Active.Value);
+            AddAssert("MR panel active", () => getPanelForMod(typeof(OsuModMirror)).Active.Value);
         }
 
         [Test]
@@ -169,6 +183,206 @@ namespace osu.Game.Tests.Visual.UserInterface
             assertCustomisationToggleState(disabled: true, active: false); // config was dismissed without explicit user action.
         }
 
+        /// <summary>
+        /// Ensure that two mod overlays are not cross polluting via central settings instances.
+        /// </summary>
+        [Test]
+        public void TestSettingsNotCrossPolluting()
+        {
+            Bindable<IReadOnlyList<Mod>> selectedMods2 = null;
+            ModSelectScreen modSelectScreen2 = null;
+
+            createScreen();
+            AddStep("select diff adjust", () => SelectedMods.Value = new Mod[] { new OsuModDifficultyAdjust() });
+
+            AddStep("set setting", () => modSelectScreen.ChildrenOfType<SettingsSlider<float>>().First().Current.Value = 8);
+
+            AddAssert("ensure setting is propagated", () => SelectedMods.Value.OfType<OsuModDifficultyAdjust>().Single().CircleSize.Value == 8);
+
+            AddStep("create second bindable", () => selectedMods2 = new Bindable<IReadOnlyList<Mod>>(new Mod[] { new OsuModDifficultyAdjust() }));
+
+            AddStep("create second overlay", () =>
+            {
+                Add(modSelectScreen2 = new UserModSelectScreen().With(d =>
+                {
+                    d.Origin = Anchor.TopCentre;
+                    d.Anchor = Anchor.TopCentre;
+                    d.SelectedMods.BindTarget = selectedMods2;
+                }));
+            });
+
+            AddStep("show", () => modSelectScreen2.Show());
+
+            AddAssert("ensure first is unchanged", () => SelectedMods.Value.OfType<OsuModDifficultyAdjust>().Single().CircleSize.Value == 8);
+            AddAssert("ensure second is default", () => selectedMods2.Value.OfType<OsuModDifficultyAdjust>().Single().CircleSize.Value == null);
+        }
+
+        [Test]
+        public void TestSettingsResetOnDeselection()
+        {
+            var osuModDoubleTime = new OsuModDoubleTime { SpeedChange = { Value = 1.2 } };
+
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("set dt mod with custom rate", () => { SelectedMods.Value = new[] { osuModDoubleTime }; });
+
+            AddAssert("selected mod matches", () => (SelectedMods.Value.Single() as OsuModDoubleTime)?.SpeedChange.Value == 1.2);
+
+            AddStep("deselect", () => getPanelForMod(typeof(OsuModDoubleTime)).TriggerClick());
+            AddAssert("selected mods empty", () => SelectedMods.Value.Count == 0);
+
+            AddStep("reselect", () => getPanelForMod(typeof(OsuModDoubleTime)).TriggerClick());
+            AddAssert("selected mod has default value", () => (SelectedMods.Value.Single() as OsuModDoubleTime)?.SpeedChange.IsDefault == true);
+        }
+
+        [Test]
+        public void TestAnimationFlushOnClose()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("Select all fun mods", () =>
+            {
+                modSelectScreen.ChildrenOfType<ModColumn>()
+                               .Single(c => c.ModType == ModType.DifficultyIncrease)
+                               .SelectAll();
+            });
+
+            AddUntilStep("many mods selected", () => SelectedMods.Value.Count >= 5);
+
+            AddStep("trigger deselect and close overlay", () =>
+            {
+                modSelectScreen.ChildrenOfType<ModColumn>()
+                               .Single(c => c.ModType == ModType.DifficultyIncrease)
+                               .DeselectAll();
+
+                modSelectScreen.Hide();
+            });
+
+            AddAssert("all mods deselected", () => SelectedMods.Value.Count == 0);
+        }
+
+        [Test]
+        public void TestRulesetChanges()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            var noFailMod = new OsuRuleset().GetModsFor(ModType.DifficultyReduction).FirstOrDefault(m => m is OsuModNoFail);
+
+            AddStep("set mods externally", () => { SelectedMods.Value = new[] { noFailMod }; });
+
+            changeRuleset(0);
+
+            AddAssert("ensure mods still selected", () => SelectedMods.Value.SingleOrDefault(m => m is OsuModNoFail) != null);
+
+            changeRuleset(3);
+
+            AddAssert("ensure mods not selected", () => SelectedMods.Value.Count == 0);
+
+            changeRuleset(0);
+
+            AddAssert("ensure mods not selected", () => SelectedMods.Value.Count == 0);
+        }
+
+        [Test]
+        public void TestExternallySetCustomizedMod()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("set customized mod externally", () => SelectedMods.Value = new[] { new OsuModDoubleTime { SpeedChange = { Value = 1.01 } } });
+
+            AddAssert("ensure button is selected and customized accordingly", () =>
+            {
+                var button = getPanelForMod(SelectedMods.Value.Single().GetType());
+                return ((OsuModDoubleTime)button.Mod).SpeedChange.Value == 1.01;
+            });
+        }
+
+        [Test]
+        public void TestSettingsAreRetainedOnReload()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("set customized mod externally", () => SelectedMods.Value = new[] { new OsuModDoubleTime { SpeedChange = { Value = 1.01 } } });
+            AddAssert("setting remains", () => (SelectedMods.Value.SingleOrDefault() as OsuModDoubleTime)?.SpeedChange.Value == 1.01);
+
+            createScreen();
+            AddAssert("setting remains", () => (SelectedMods.Value.SingleOrDefault() as OsuModDoubleTime)?.SpeedChange.Value == 1.01);
+        }
+
+        [Test]
+        public void TestExternallySetModIsReplacedByOverlayInstance()
+        {
+            Mod external = new OsuModDoubleTime();
+            Mod overlayButtonMod = null;
+
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("set mod externally", () => { SelectedMods.Value = new[] { external }; });
+
+            AddAssert("ensure button is selected", () =>
+            {
+                var button = getPanelForMod(SelectedMods.Value.Single().GetType());
+                overlayButtonMod = button.Mod;
+                return button.Active.Value;
+            });
+
+            // Right now, when an external change occurs, the ModSelectOverlay will replace the global instance with its own
+            AddAssert("mod instance doesn't match", () => external != overlayButtonMod);
+
+            AddAssert("one mod present in global selected", () => SelectedMods.Value.Count == 1);
+            AddAssert("globally selected matches button's mod instance", () => SelectedMods.Value.Any(mod => ReferenceEquals(mod, overlayButtonMod)));
+            AddAssert("globally selected doesn't contain original external change", () => !SelectedMods.Value.Any(mod => ReferenceEquals(mod, external)));
+        }
+
+        [Test]
+        public void TestChangeIsValidChangesButtonVisibility()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddAssert("double time visible", () => modSelectScreen.ChildrenOfType<ModPanel>().Where(panel => panel.Mod is OsuModDoubleTime).Any(panel => !panel.Filtered.Value));
+
+            AddStep("make double time invalid", () => modSelectScreen.IsValidMod = m => !(m is OsuModDoubleTime));
+            AddUntilStep("double time not visible", () => modSelectScreen.ChildrenOfType<ModPanel>().Where(panel => panel.Mod is OsuModDoubleTime).All(panel => panel.Filtered.Value));
+            AddAssert("nightcore still visible", () => modSelectScreen.ChildrenOfType<ModPanel>().Where(panel => panel.Mod is OsuModNightcore).Any(panel => !panel.Filtered.Value));
+
+            AddStep("make double time valid again", () => modSelectScreen.IsValidMod = m => true);
+            AddUntilStep("double time visible", () => modSelectScreen.ChildrenOfType<ModPanel>().Where(panel => panel.Mod is OsuModDoubleTime).Any(panel => !panel.Filtered.Value));
+            AddAssert("nightcore still visible", () => modSelectScreen.ChildrenOfType<ModPanel>().Where(b => b.Mod is OsuModNightcore).Any(panel => !panel.Filtered.Value));
+        }
+
+        [Test]
+        public void TestChangeIsValidPreservesSelection()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("select DT + HD", () => SelectedMods.Value = new Mod[] { new OsuModDoubleTime(), new OsuModHidden() });
+            AddAssert("DT + HD selected", () => modSelectScreen.ChildrenOfType<ModPanel>().Count(panel => panel.Active.Value) == 2);
+
+            AddStep("make NF invalid", () => modSelectScreen.IsValidMod = m => !(m is ModNoFail));
+            AddAssert("DT + HD still selected", () => modSelectScreen.ChildrenOfType<ModPanel>().Count(panel => panel.Active.Value) == 2);
+        }
+
+        [Test]
+        public void TestUnimplementedModIsUnselectable()
+        {
+            var testRuleset = new TestUnimplementedModOsuRuleset();
+
+            createScreen();
+
+            AddStep("set ruleset", () => Ruleset.Value = testRuleset.RulesetInfo);
+            waitForColumnLoad();
+
+            AddAssert("unimplemented mod panel is filtered", () => getPanelForMod(typeof(TestUnimplementedMod)).Filtered.Value);
+        }
+
         private void waitForColumnLoad() => AddUntilStep("all column content loaded",
             () => modSelectScreen.ChildrenOfType<ModColumn>().Any() && modSelectScreen.ChildrenOfType<ModColumn>().All(column => column.IsLoaded && column.ItemsLoaded));
 
@@ -188,5 +402,26 @@ namespace osu.Game.Tests.Visual.UserInterface
 
         private ModPanel getPanelForMod(Type modType)
             => modSelectScreen.ChildrenOfType<ModPanel>().Single(panel => panel.Mod.GetType() == modType);
+
+        private class TestUnimplementedMod : Mod
+        {
+            public override string Name => "Unimplemented mod";
+            public override string Acronym => "UM";
+            public override string Description => "A mod that is not implemented.";
+            public override double ScoreMultiplier => 1;
+            public override ModType Type => ModType.Conversion;
+        }
+
+        private class TestUnimplementedModOsuRuleset : OsuRuleset
+        {
+            public override string ShortName => "unimplemented";
+
+            public override IEnumerable<Mod> GetModsFor(ModType type)
+            {
+                if (type == ModType.Conversion) return base.GetModsFor(type).Concat(new[] { new TestUnimplementedMod() });
+
+                return base.GetModsFor(type);
+            }
+        }
     }
 }
diff --git a/osu.Game/Input/Bindings/GlobalActionContainer.cs b/osu.Game/Input/Bindings/GlobalActionContainer.cs
index 9cb8f2dfcc..13a3f006fb 100644
--- a/osu.Game/Input/Bindings/GlobalActionContainer.cs
+++ b/osu.Game/Input/Bindings/GlobalActionContainer.cs
@@ -82,6 +82,8 @@ namespace osu.Game.Input.Bindings
             new KeyBinding(new[] { InputKey.F5 }, GlobalAction.EditorTestGameplay),
             new KeyBinding(new[] { InputKey.Control, InputKey.H }, GlobalAction.EditorFlipHorizontally),
             new KeyBinding(new[] { InputKey.Control, InputKey.J }, GlobalAction.EditorFlipVertically),
+            new KeyBinding(new[] { InputKey.Control, InputKey.Alt, InputKey.MouseWheelDown }, GlobalAction.EditorDecreaseDistanceSpacing),
+            new KeyBinding(new[] { InputKey.Control, InputKey.Alt, InputKey.MouseWheelUp }, GlobalAction.EditorIncreaseDistanceSpacing),
         };
 
         public IEnumerable<KeyBinding> InGameKeyBindings => new[]
@@ -305,6 +307,12 @@ namespace osu.Game.Input.Bindings
         [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.EditorFlipVertically))]
         EditorFlipVertically,
 
+        [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.EditorIncreaseDistanceSpacing))]
+        EditorIncreaseDistanceSpacing,
+
+        [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.EditorDecreaseDistanceSpacing))]
+        EditorDecreaseDistanceSpacing,
+
         [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.SelectPreviousGroup))]
         SelectPreviousGroup,
 
diff --git a/osu.Game/Localisation/GlobalActionKeyBindingStrings.cs b/osu.Game/Localisation/GlobalActionKeyBindingStrings.cs
index 129706261b..cfe0fd55ce 100644
--- a/osu.Game/Localisation/GlobalActionKeyBindingStrings.cs
+++ b/osu.Game/Localisation/GlobalActionKeyBindingStrings.cs
@@ -249,6 +249,16 @@ namespace osu.Game.Localisation
         /// </summary>
         public static LocalisableString EditorFlipVertically => new TranslatableString(getKey(@"editor_flip_vertically"), @"Flip selection vertically");
 
+        /// <summary>
+        /// "Increase distance spacing"
+        /// </summary>
+        public static LocalisableString EditorIncreaseDistanceSpacing => new TranslatableString(getKey(@"editor_increase_distance_spacing"), @"Increase distance spacing");
+
+        /// <summary>
+        /// "Decrease distance spacing"
+        /// </summary>
+        public static LocalisableString EditorDecreaseDistanceSpacing => new TranslatableString(getKey(@"editor_decrease_distance_spacing"), @"Decrease distance spacing");
+
         /// <summary>
         /// "Toggle skin editor"
         /// </summary>
diff --git a/osu.Game/Overlays/Mods/ModColumn.cs b/osu.Game/Overlays/Mods/ModColumn.cs
index 018922c074..a792c0a81e 100644
--- a/osu.Game/Overlays/Mods/ModColumn.cs
+++ b/osu.Game/Overlays/Mods/ModColumn.cs
@@ -1,6 +1,8 @@
 // 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.
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -10,6 +12,7 @@ using Humanizer;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Extensions.Color4Extensions;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Colour;
 using osu.Framework.Graphics.Containers;
@@ -25,8 +28,6 @@ using osuTK;
 using osuTK.Graphics;
 using osuTK.Input;
 
-#nullable enable
-
 namespace osu.Game.Overlays.Mods
 {
     public class ModColumn : CompositeDrawable
@@ -52,9 +53,22 @@ namespace osu.Game.Overlays.Mods
             }
         }
 
-        public Bindable<IReadOnlyList<Mod>> SelectedMods = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
         public Bindable<bool> Active = new BindableBool(true);
 
+        /// <summary>
+        /// List of mods marked as selected in this column.
+        /// </summary>
+        /// <remarks>
+        /// Note that the mod instances returned by this property are owned solely by this column
+        /// (as in, they are locally-managed clones, to ensure proper isolation from any other external instances).
+        /// </remarks>
+        public IReadOnlyList<Mod> SelectedMods { get; private set; } = Array.Empty<Mod>();
+
+        /// <summary>
+        /// Invoked when a mod panel has been selected interactively by the user.
+        /// </summary>
+        public event Action? SelectionChangedByUser;
+
         protected override bool ReceivePositionalInputAtSubTree(Vector2 screenSpacePos) => base.ReceivePositionalInputAtSubTree(screenSpacePos) && Active.Value;
 
         protected virtual ModPanel CreateModPanel(Mod mod) => new ModPanel(mod);
@@ -63,6 +77,15 @@ namespace osu.Game.Overlays.Mods
 
         private readonly Bindable<Dictionary<ModType, IReadOnlyList<Mod>>> availableMods = new Bindable<Dictionary<ModType, IReadOnlyList<Mod>>>();
 
+        /// <summary>
+        /// All mods that are available for the current ruleset in this particular column.
+        /// </summary>
+        /// <remarks>
+        /// Note that the mod instances in this list are owned solely by this column
+        /// (as in, they are locally-managed clones, to ensure proper isolation from any other external instances).
+        /// </remarks>
+        private IReadOnlyList<Mod> localAvailableMods = Array.Empty<Mod>();
+
         private readonly TextFlowContainer headerText;
         private readonly Box headerBackground;
         private readonly Container contentContainer;
@@ -226,6 +249,9 @@ namespace osu.Game.Overlays.Mods
         private void load(OsuGameBase game, OverlayColourProvider colourProvider, OsuColour colours)
         {
             availableMods.BindTo(game.AvailableMods);
+            // this `BindValueChanged` callback is intentionally here, to ensure that local available mods are constructed as early as possible.
+            // this is needed to make sure no external changes to mods are dropped while mod panels are asynchronously loading.
+            availableMods.BindValueChanged(_ => updateLocalAvailableMods(), true);
 
             headerBackground.Colour = accentColour = colours.ForModType(ModType);
 
@@ -239,31 +265,26 @@ namespace osu.Game.Overlays.Mods
             contentBackground.Colour = colourProvider.Background4;
         }
 
-        protected override void LoadComplete()
+        private void updateLocalAvailableMods()
         {
-            base.LoadComplete();
-            availableMods.BindValueChanged(_ => Scheduler.AddOnce(updateMods));
-            SelectedMods.BindValueChanged(_ =>
-            {
-                // if a load is in progress, don't try to update the selection - the load flow will do so.
-                if (latestLoadTask == null)
-                    updateActiveState();
-            });
-            updateMods();
+            var newMods = ModUtils.FlattenMods(availableMods.Value.GetValueOrDefault(ModType) ?? Array.Empty<Mod>())
+                                  .Select(m => m.DeepClone())
+                                  .ToList();
+
+            if (newMods.SequenceEqual(localAvailableMods))
+                return;
+
+            localAvailableMods = newMods;
+            Scheduler.AddOnce(loadPanels);
         }
 
         private CancellationTokenSource? cancellationTokenSource;
 
-        private void updateMods()
+        private void loadPanels()
         {
-            var newMods = ModUtils.FlattenMods(availableMods.Value.GetValueOrDefault(ModType) ?? Array.Empty<Mod>()).ToList();
-
-            if (newMods.SequenceEqual(panelFlow.Children.Select(p => p.Mod)))
-                return;
-
             cancellationTokenSource?.Cancel();
 
-            var panels = newMods.Select(mod => CreateModPanel(mod).With(panel => panel.Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0)));
+            var panels = localAvailableMods.Select(mod => CreateModPanel(mod).With(panel => panel.Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0)));
 
             Task? loadTask;
 
@@ -277,13 +298,7 @@ namespace osu.Game.Overlays.Mods
 
                 foreach (var panel in panelFlow)
                 {
-                    panel.Active.BindValueChanged(_ =>
-                    {
-                        updateToggleAllState();
-                        SelectedMods.Value = panel.Active.Value
-                            ? SelectedMods.Value.Append(panel.Mod).ToArray()
-                            : SelectedMods.Value.Except(new[] { panel.Mod }).ToArray();
-                    });
+                    panel.Active.BindValueChanged(_ => panelStateChanged(panel));
                 }
             }, (cancellationTokenSource = new CancellationTokenSource()).Token);
             loadTask.ContinueWith(_ =>
@@ -296,7 +311,62 @@ namespace osu.Game.Overlays.Mods
         private void updateActiveState()
         {
             foreach (var panel in panelFlow)
-                panel.Active.Value = SelectedMods.Value.Contains(panel.Mod, EqualityComparer<Mod>.Default);
+                panel.Active.Value = SelectedMods.Contains(panel.Mod);
+        }
+
+        /// <summary>
+        /// This flag helps to determine the source of changes to <see cref="SelectedMods"/>.
+        /// If the value is false, then <see cref="SelectedMods"/> are changing due to a user selection on the UI.
+        /// If the value is true, then <see cref="SelectedMods"/> are changing due to an external <see cref="SetSelection"/> call.
+        /// </summary>
+        private bool externalSelectionUpdateInProgress;
+
+        private void panelStateChanged(ModPanel panel)
+        {
+            updateToggleAllState();
+
+            var newSelectedMods = panel.Active.Value
+                ? SelectedMods.Append(panel.Mod)
+                : SelectedMods.Except(panel.Mod.Yield());
+
+            SelectedMods = newSelectedMods.ToArray();
+            if (!externalSelectionUpdateInProgress)
+                SelectionChangedByUser?.Invoke();
+        }
+
+        /// <summary>
+        /// Adjusts the set of selected mods in this column to match the passed in <paramref name="mods"/>.
+        /// </summary>
+        /// <remarks>
+        /// This method exists to be able to receive mod instances that come from potentially-external sources and to copy the changes across to this column's state.
+        /// <see cref="ModSelectScreen"/> uses this to substitute any external mod references in <see cref="ModSelectScreen.SelectedMods"/>
+        /// to references that are owned by this column.
+        /// </remarks>
+        internal void SetSelection(IReadOnlyList<Mod> mods)
+        {
+            externalSelectionUpdateInProgress = true;
+
+            var newSelection = new List<Mod>();
+
+            foreach (var mod in localAvailableMods)
+            {
+                var matchingSelectedMod = mods.SingleOrDefault(selected => selected.GetType() == mod.GetType());
+
+                if (matchingSelectedMod != null)
+                {
+                    mod.CopyFrom(matchingSelectedMod);
+                    newSelection.Add(mod);
+                }
+                else
+                {
+                    mod.ResetSettingsToDefaults();
+                }
+            }
+
+            SelectedMods = newSelection;
+            updateActiveState();
+
+            externalSelectionUpdateInProgress = false;
         }
 
         #region Bulk select / deselect
@@ -364,6 +434,15 @@ namespace osu.Game.Overlays.Mods
                 pendingSelectionOperations.Enqueue(() => button.Active.Value = false);
         }
 
+        /// <summary>
+        /// Run any delayed selections (due to animation) immediately to leave mods in a good (final) state.
+        /// </summary>
+        public void FlushPendingSelections()
+        {
+            while (pendingSelectionOperations.TryDequeue(out var dequeuedAction))
+                dequeuedAction();
+        }
+
         private class ToggleAllCheckbox : OsuCheckbox
         {
             private Color4 accentColour;
diff --git a/osu.Game/Overlays/Mods/ModSection.cs b/osu.Game/Overlays/Mods/ModSection.cs
index 5bf8cddd0c..a70191a864 100644
--- a/osu.Game/Overlays/Mods/ModSection.cs
+++ b/osu.Game/Overlays/Mods/ModSection.cs
@@ -250,9 +250,9 @@ namespace osu.Game.Overlays.Mods
         protected virtual ModButton CreateModButton(Mod mod) => new ModButton(mod);
 
         /// <summary>
-        /// Play out all remaining animations immediately to leave mods in a good (final) state.
+        /// Run any delayed selections (due to animation) immediately to leave mods in a good (final) state.
         /// </summary>
-        public void FlushAnimation()
+        public void FlushPendingSelections()
         {
             while (pendingSelectionOperations.TryDequeue(out var dequeuedAction))
                 dequeuedAction();
diff --git a/osu.Game/Overlays/Mods/ModSelectOverlay.cs b/osu.Game/Overlays/Mods/ModSelectOverlay.cs
index 9ce79c25f7..cf57322594 100644
--- a/osu.Game/Overlays/Mods/ModSelectOverlay.cs
+++ b/osu.Game/Overlays/Mods/ModSelectOverlay.cs
@@ -369,7 +369,7 @@ namespace osu.Game.Overlays.Mods
 
             foreach (var section in ModSectionsContainer)
             {
-                section.FlushAnimation();
+                section.FlushPendingSelections();
             }
 
             FooterContainer.MoveToX(content_width, WaveContainer.DISAPPEAR_DURATION, Easing.InSine);
diff --git a/osu.Game/Overlays/Mods/ModSelectScreen.cs b/osu.Game/Overlays/Mods/ModSelectScreen.cs
index ffd6e9a52c..8060bca65f 100644
--- a/osu.Game/Overlays/Mods/ModSelectScreen.cs
+++ b/osu.Game/Overlays/Mods/ModSelectScreen.cs
@@ -179,7 +179,7 @@ namespace osu.Game.Overlays.Mods
 
             foreach (var column in columnFlow.Columns)
             {
-                column.SelectedMods.BindValueChanged(updateBindableFromSelection);
+                column.SelectionChangedByUser += updateBindableFromSelection;
             }
 
             customisationVisible.BindValueChanged(_ => updateCustomisationVisualState(), true);
@@ -203,7 +203,7 @@ namespace osu.Game.Overlays.Mods
         private void updateAvailableMods()
         {
             foreach (var column in columnFlow.Columns)
-                column.Filter = isValidMod;
+                column.Filter = m => m.HasImplementation && isValidMod.Invoke(m);
         }
 
         private void updateCustomisation(ValueChangedEvent<IReadOnlyList<Mod>> valueChangedEvent)
@@ -250,33 +250,26 @@ namespace osu.Game.Overlays.Mods
 
         private void updateSelectionFromBindable()
         {
-            // note that selectionBindableSyncInProgress is purposefully not checked here.
-            // this is because in the case of mod selection in solo gameplay, a user selection of a mod can actually lead to deselection of other incompatible mods.
-            // to synchronise state correctly, updateBindableFromSelection() computes the final mods (including incompatibility rules) and updates SelectedMods,
-            // and this method then runs unconditionally again to make sure the new visual selection accurately reflects the final set of selected mods.
-            // selectionBindableSyncInProgress ensures that mutual infinite recursion does not happen after that unconditional call.
+            // `SelectedMods` may contain mod references that come from external sources.
+            // to ensure isolation, first pull in the potentially-external change into the mod columns...
             foreach (var column in columnFlow.Columns)
-                column.SelectedMods.Value = SelectedMods.Value.Where(mod => mod.Type == column.ModType).ToArray();
+                column.SetSelection(SelectedMods.Value);
+
+            // and then, when done, replace the potentially-external mod references in `SelectedMods` with ones we own.
+            updateBindableFromSelection();
         }
 
-        private bool selectionBindableSyncInProgress;
-
-        private void updateBindableFromSelection(ValueChangedEvent<IReadOnlyList<Mod>> modSelectionChange)
+        private void updateBindableFromSelection()
         {
-            if (selectionBindableSyncInProgress)
+            var candidateSelection = columnFlow.Columns.SelectMany(column => column.SelectedMods).ToArray();
+
+            if (candidateSelection.SequenceEqual(SelectedMods.Value))
                 return;
 
-            selectionBindableSyncInProgress = true;
-
-            SelectedMods.Value = ComputeNewModsFromSelection(
-                modSelectionChange.NewValue.Except(modSelectionChange.OldValue),
-                modSelectionChange.OldValue.Except(modSelectionChange.NewValue));
-
-            selectionBindableSyncInProgress = false;
+            SelectedMods.Value = ComputeNewModsFromSelection(SelectedMods.Value, candidateSelection);
         }
 
-        protected virtual IReadOnlyList<Mod> ComputeNewModsFromSelection(IEnumerable<Mod> addedMods, IEnumerable<Mod> removedMods)
-            => columnFlow.Columns.SelectMany(column => column.SelectedMods.Value).ToArray();
+        protected virtual IReadOnlyList<Mod> ComputeNewModsFromSelection(IReadOnlyList<Mod> oldSelection, IReadOnlyList<Mod> newSelection) => newSelection;
 
         protected override void PopIn()
         {
@@ -313,10 +306,12 @@ namespace osu.Game.Overlays.Mods
             {
                 const float distance = 700;
 
-                columnFlow[i].Column
-                             .TopLevelContent
-                             .MoveToY(i % 2 == 0 ? -distance : distance, fade_out_duration, Easing.OutQuint)
-                             .FadeOut(fade_out_duration, Easing.OutQuint);
+                var column = columnFlow[i].Column;
+
+                column.FlushPendingSelections();
+                column.TopLevelContent
+                      .MoveToY(i % 2 == 0 ? -distance : distance, fade_out_duration, Easing.OutQuint)
+                      .FadeOut(fade_out_duration, Easing.OutQuint);
             }
         }
 
diff --git a/osu.Game/Overlays/Mods/ModSettingsArea.cs b/osu.Game/Overlays/Mods/ModSettingsArea.cs
index be72c1e3e3..9c5f3b7f11 100644
--- a/osu.Game/Overlays/Mods/ModSettingsArea.cs
+++ b/osu.Game/Overlays/Mods/ModSettingsArea.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;
 using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Allocation;
@@ -21,7 +22,7 @@ namespace osu.Game.Overlays.Mods
 {
     public class ModSettingsArea : CompositeDrawable
     {
-        public Bindable<IReadOnlyList<Mod>> SelectedMods { get; } = new Bindable<IReadOnlyList<Mod>>();
+        public Bindable<IReadOnlyList<Mod>> SelectedMods { get; } = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
 
         public const float HEIGHT = 250;
 
@@ -77,7 +78,7 @@ namespace osu.Game.Overlays.Mods
         protected override void LoadComplete()
         {
             base.LoadComplete();
-            SelectedMods.BindValueChanged(_ => updateMods());
+            SelectedMods.BindValueChanged(_ => updateMods(), true);
         }
 
         private void updateMods()
diff --git a/osu.Game/Overlays/Mods/UserModSelectScreen.cs b/osu.Game/Overlays/Mods/UserModSelectScreen.cs
index ed0a07521b..ca33d35605 100644
--- a/osu.Game/Overlays/Mods/UserModSelectScreen.cs
+++ b/osu.Game/Overlays/Mods/UserModSelectScreen.cs
@@ -14,9 +14,12 @@ namespace osu.Game.Overlays.Mods
     {
         protected override ModColumn CreateModColumn(ModType modType, Key[] toggleKeys = null) => new UserModColumn(modType, false, toggleKeys);
 
-        protected override IReadOnlyList<Mod> ComputeNewModsFromSelection(IEnumerable<Mod> addedMods, IEnumerable<Mod> removedMods)
+        protected override IReadOnlyList<Mod> ComputeNewModsFromSelection(IReadOnlyList<Mod> oldSelection, IReadOnlyList<Mod> newSelection)
         {
-            IEnumerable<Mod> modsAfterRemoval = SelectedMods.Value.Except(removedMods).ToList();
+            var addedMods = newSelection.Except(oldSelection);
+            var removedMods = oldSelection.Except(newSelection);
+
+            IEnumerable<Mod> modsAfterRemoval = newSelection.Except(removedMods).ToList();
 
             // the preference is that all new mods should override potential incompatible old mods.
             // in general that's a bit difficult to compute if more than one mod is added at a time,
diff --git a/osu.Game/Rulesets/Edit/DistancedHitObjectComposer.cs b/osu.Game/Rulesets/Edit/DistancedHitObjectComposer.cs
index 0505f9ab0e..680fc9aaa8 100644
--- a/osu.Game/Rulesets/Edit/DistancedHitObjectComposer.cs
+++ b/osu.Game/Rulesets/Edit/DistancedHitObjectComposer.cs
@@ -3,13 +3,19 @@
 
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
+using osu.Framework.Extensions;
+using osu.Framework.Extensions.LocalisationExtensions;
 using osu.Framework.Graphics;
+using osu.Framework.Input.Bindings;
 using osu.Framework.Input.Events;
-using osu.Game.Graphics.Containers;
+using osu.Framework.Localisation;
+using osu.Game.Configuration;
 using osu.Game.Graphics.UserInterface;
+using osu.Game.Input.Bindings;
+using osu.Game.Overlays;
+using osu.Game.Overlays.OSD;
 using osu.Game.Overlays.Settings.Sections;
 using osu.Game.Rulesets.Objects;
-using osuTK;
 
 namespace osu.Game.Rulesets.Edit
 {
@@ -18,7 +24,7 @@ namespace osu.Game.Rulesets.Edit
     /// </summary>
     /// <typeparam name="TObject">The base type of supported objects.</typeparam>
     [Cached(typeof(IDistanceSnapProvider))]
-    public abstract class DistancedHitObjectComposer<TObject> : HitObjectComposer<TObject>, IDistanceSnapProvider
+    public abstract class DistancedHitObjectComposer<TObject> : HitObjectComposer<TObject>, IDistanceSnapProvider, IScrollBindingHandler<GlobalAction>
         where TObject : HitObject
     {
         protected Bindable<double> DistanceSpacingMultiplier { get; } = new BindableDouble(1.0)
@@ -33,7 +39,9 @@ namespace osu.Game.Rulesets.Edit
         protected ExpandingToolboxContainer RightSideToolboxContainer { get; private set; }
 
         private ExpandableSlider<double, SizeSlider<double>> distanceSpacingSlider;
-        private bool distanceSpacingScrollActive;
+
+        [Resolved(canBeNull: true)]
+        private OnScreenDisplay onScreenDisplay { get; set; }
 
         protected DistancedHitObjectComposer(Ruleset ruleset)
             : base(ruleset)
@@ -43,8 +51,9 @@ namespace osu.Game.Rulesets.Edit
         [BackgroundDependencyLoader]
         private void load()
         {
-            AddInternal(RightSideToolboxContainer = new ExpandingToolboxContainer
+            AddInternal(RightSideToolboxContainer = new ExpandingToolboxContainer(130, 250)
             {
+                Padding = new MarginPadding { Right = 10 },
                 Alpha = DistanceSpacingMultiplier.Disabled ? 0 : 1,
                 Anchor = Anchor.TopRight,
                 Origin = Anchor.TopRight,
@@ -66,45 +75,58 @@ namespace osu.Game.Rulesets.Edit
             if (!DistanceSpacingMultiplier.Disabled)
             {
                 DistanceSpacingMultiplier.Value = EditorBeatmap.BeatmapInfo.DistanceSpacing;
-                DistanceSpacingMultiplier.BindValueChanged(v =>
+                DistanceSpacingMultiplier.BindValueChanged(multiplier =>
                 {
-                    distanceSpacingSlider.ContractedLabelText = $"D. S. ({v.NewValue:0.##x})";
-                    distanceSpacingSlider.ExpandedLabelText = $"Distance Spacing ({v.NewValue:0.##x})";
-                    EditorBeatmap.BeatmapInfo.DistanceSpacing = v.NewValue;
+                    distanceSpacingSlider.ContractedLabelText = $"D. S. ({multiplier.NewValue:0.##x})";
+                    distanceSpacingSlider.ExpandedLabelText = $"Distance Spacing ({multiplier.NewValue:0.##x})";
+
+                    if (multiplier.NewValue != multiplier.OldValue)
+                        onScreenDisplay?.Display(new DistanceSpacingToast(multiplier.NewValue.ToLocalisableString(@"0.##x"), multiplier));
+
+                    EditorBeatmap.BeatmapInfo.DistanceSpacing = multiplier.NewValue;
                 }, true);
             }
         }
 
-        protected override bool OnKeyDown(KeyDownEvent e)
+        public bool OnPressed(KeyBindingPressEvent<GlobalAction> e)
         {
-            if (!DistanceSpacingMultiplier.Disabled && e.ControlPressed && e.AltPressed && !e.Repeat)
+            switch (e.Action)
             {
-                RightSideToolboxContainer.Expanded.Value = true;
-                distanceSpacingScrollActive = true;
-                return true;
+                case GlobalAction.EditorIncreaseDistanceSpacing:
+                case GlobalAction.EditorDecreaseDistanceSpacing:
+                    return adjustDistanceSpacing(e.Action, 0.1f);
             }
 
-            return base.OnKeyDown(e);
+            return false;
         }
 
-        protected override void OnKeyUp(KeyUpEvent e)
+        public void OnReleased(KeyBindingReleaseEvent<GlobalAction> e)
         {
-            if (!DistanceSpacingMultiplier.Disabled && distanceSpacingScrollActive && (!e.AltPressed || !e.ControlPressed))
-            {
-                RightSideToolboxContainer.Expanded.Value = false;
-                distanceSpacingScrollActive = false;
-            }
         }
 
-        protected override bool OnScroll(ScrollEvent e)
+        public bool OnScroll(KeyBindingScrollEvent<GlobalAction> e)
         {
-            if (distanceSpacingScrollActive)
+            switch (e.Action)
             {
-                DistanceSpacingMultiplier.Value += e.ScrollDelta.Y * (e.IsPrecise ? 0.01f : 0.1f);
-                return true;
+                case GlobalAction.EditorIncreaseDistanceSpacing:
+                case GlobalAction.EditorDecreaseDistanceSpacing:
+                    return adjustDistanceSpacing(e.Action, e.ScrollAmount * (e.IsPrecise ? 0.01f : 0.1f));
             }
 
-            return base.OnScroll(e);
+            return false;
+        }
+
+        private bool adjustDistanceSpacing(GlobalAction action, float amount)
+        {
+            if (DistanceSpacingMultiplier.Disabled)
+                return false;
+
+            if (action == GlobalAction.EditorIncreaseDistanceSpacing)
+                DistanceSpacingMultiplier.Value += amount;
+            else if (action == GlobalAction.EditorDecreaseDistanceSpacing)
+                DistanceSpacingMultiplier.Value -= amount;
+
+            return true;
         }
 
         public virtual float GetBeatSnapDistanceAt(HitObject referenceObject)
@@ -145,18 +167,25 @@ namespace osu.Game.Rulesets.Edit
             return DurationToDistance(referenceObject, snappedEndTime - startTime);
         }
 
-        protected class ExpandingToolboxContainer : ExpandingContainer
+        private class DistanceSpacingToast : Toast
         {
-            protected override double HoverExpansionDelay => 250;
+            private readonly ValueChangedEvent<double> change;
 
-            public ExpandingToolboxContainer()
-                : base(130, 250)
+            public DistanceSpacingToast(LocalisableString value, ValueChangedEvent<double> change)
+                : base(getAction(change).GetLocalisableDescription(), value, string.Empty)
             {
-                RelativeSizeAxes = Axes.Y;
-                Padding = new MarginPadding { Left = 10 };
-
-                FillFlow.Spacing = new Vector2(10);
+                this.change = change;
             }
+
+            [BackgroundDependencyLoader]
+            private void load(OsuConfigManager config)
+            {
+                ShortcutText.Text = config.LookupKeyBindings(getAction(change)).ToUpper();
+            }
+
+            private static GlobalAction getAction(ValueChangedEvent<double> change) => change.NewValue - change.OldValue > 0
+                ? GlobalAction.EditorIncreaseDistanceSpacing
+                : GlobalAction.EditorDecreaseDistanceSpacing;
         }
     }
 }
diff --git a/osu.Game/Rulesets/Edit/ExpandingToolboxContainer.cs b/osu.Game/Rulesets/Edit/ExpandingToolboxContainer.cs
new file mode 100644
index 0000000000..e807dbd482
--- /dev/null
+++ b/osu.Game/Rulesets/Edit/ExpandingToolboxContainer.cs
@@ -0,0 +1,34 @@
+// 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.Linq;
+using osu.Framework.Graphics;
+using osu.Framework.Input.Events;
+using osu.Game.Graphics.Containers;
+using osuTK;
+
+namespace osu.Game.Rulesets.Edit
+{
+    public class ExpandingToolboxContainer : ExpandingContainer
+    {
+        protected override double HoverExpansionDelay => 250;
+
+        public ExpandingToolboxContainer(float contractedWidth, float expandedWidth)
+            : base(contractedWidth, expandedWidth)
+        {
+            RelativeSizeAxes = Axes.Y;
+
+            FillFlow.Spacing = new Vector2(10);
+        }
+
+        protected override bool ReceivePositionalInputAtSubTree(Vector2 screenSpacePos) => base.ReceivePositionalInputAtSubTree(screenSpacePos) && anyToolboxHovered(screenSpacePos);
+
+        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => base.ReceivePositionalInputAt(screenSpacePos) && anyToolboxHovered(screenSpacePos);
+
+        private bool anyToolboxHovered(Vector2 screenSpacePos) => FillFlow.Children.Any(d => d.ScreenSpaceDrawQuad.Contains(screenSpacePos));
+
+        protected override bool OnMouseDown(MouseDownEvent e) => true;
+
+        protected override bool OnClick(ClickEvent e) => true;
+    }
+}
diff --git a/osu.Game/Rulesets/Edit/HitObjectComposer.cs b/osu.Game/Rulesets/Edit/HitObjectComposer.cs
index a235a5bc60..1c388fe68f 100644
--- a/osu.Game/Rulesets/Edit/HitObjectComposer.cs
+++ b/osu.Game/Rulesets/Edit/HitObjectComposer.cs
@@ -13,7 +13,6 @@ using osu.Framework.Input;
 using osu.Framework.Input.Events;
 using osu.Framework.Logging;
 using osu.Game.Beatmaps;
-using osu.Game.Graphics.Containers;
 using osu.Game.Rulesets.Configuration;
 using osu.Game.Rulesets.Edit.Tools;
 using osu.Game.Rulesets.Mods;
@@ -115,8 +114,9 @@ namespace osu.Game.Rulesets.Edit
                                               .WithChild(BlueprintContainer = CreateBlueprintContainer())
                     }
                 },
-                new LeftToolboxFlow
+                new ExpandingToolboxContainer(80, 200)
                 {
+                    Padding = new MarginPadding { Left = 10 },
                     Children = new Drawable[]
                     {
                         new EditorToolboxGroup("toolbox (1-9)")
@@ -382,18 +382,6 @@ namespace osu.Game.Rulesets.Edit
         }
 
         #endregion
-
-        private class LeftToolboxFlow : ExpandingButtonContainer
-        {
-            public LeftToolboxFlow()
-                : base(80, 200)
-            {
-                RelativeSizeAxes = Axes.Y;
-                Padding = new MarginPadding { Right = 10 };
-
-                FillFlow.Spacing = new Vector2(10);
-            }
-        }
     }
 
     /// <summary>
diff --git a/osu.Game/Rulesets/Edit/ScrollingToolboxGroup.cs b/osu.Game/Rulesets/Edit/ScrollingToolboxGroup.cs
deleted file mode 100644
index 98e026c49a..0000000000
--- a/osu.Game/Rulesets/Edit/ScrollingToolboxGroup.cs
+++ /dev/null
@@ -1,34 +0,0 @@
-// 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 osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Game.Graphics.Containers;
-
-namespace osu.Game.Rulesets.Edit
-{
-    public class ScrollingToolboxGroup : EditorToolboxGroup
-    {
-        protected readonly OsuScrollContainer Scroll;
-
-        protected readonly FillFlowContainer FillFlow;
-
-        protected override Container<Drawable> Content { get; }
-
-        public ScrollingToolboxGroup(string title, float scrollAreaHeight)
-            : base(title)
-        {
-            base.Content.Add(Scroll = new OsuScrollContainer
-            {
-                RelativeSizeAxes = Axes.X,
-                Height = scrollAreaHeight,
-                Child = Content = FillFlow = new FillFlowContainer
-                {
-                    RelativeSizeAxes = Axes.X,
-                    AutoSizeAxes = Axes.Y,
-                    Direction = FillDirection.Vertical,
-                },
-            });
-        }
-    }
-}
diff --git a/osu.Game/Screens/Edit/Compose/Components/RectangularPositionSnapGrid.cs b/osu.Game/Screens/Edit/Compose/Components/RectangularPositionSnapGrid.cs
index 95b4b2fe53..f0d26c7b6a 100644
--- a/osu.Game/Screens/Edit/Compose/Components/RectangularPositionSnapGrid.cs
+++ b/osu.Game/Screens/Edit/Compose/Components/RectangularPositionSnapGrid.cs
@@ -2,10 +2,13 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Layout;
+using osu.Framework.Utils;
 using osuTK;
 
 namespace osu.Game.Screens.Edit.Compose.Components
@@ -72,33 +75,47 @@ namespace osu.Game.Screens.Edit.Compose.Components
             int index = 0;
             float currentPosition = startPosition;
 
-            while ((endPosition - currentPosition) * Math.Sign(step) > 0)
+            // Make lines the same width independent of display resolution.
+            float lineWidth = DrawWidth / ScreenSpaceDrawQuad.Width;
+
+            List<Box> generatedLines = new List<Box>();
+
+            while (Precision.AlmostBigger((endPosition - currentPosition) * Math.Sign(step), 0))
             {
                 var gridLine = new Box
                 {
                     Colour = Colour4.White,
-                    Alpha = index == 0 ? 0.3f : 0.1f,
-                    EdgeSmoothness = new Vector2(0.2f)
+                    Alpha = 0.1f,
                 };
 
                 if (direction == Direction.Horizontal)
                 {
+                    gridLine.Origin = Anchor.CentreLeft;
                     gridLine.RelativeSizeAxes = Axes.X;
-                    gridLine.Height = 1;
+                    gridLine.Height = lineWidth;
                     gridLine.Y = currentPosition;
                 }
                 else
                 {
+                    gridLine.Origin = Anchor.TopCentre;
                     gridLine.RelativeSizeAxes = Axes.Y;
-                    gridLine.Width = 1;
+                    gridLine.Width = lineWidth;
                     gridLine.X = currentPosition;
                 }
 
-                AddInternal(gridLine);
+                generatedLines.Add(gridLine);
 
                 index += 1;
                 currentPosition = startPosition + index * step;
             }
+
+            if (generatedLines.Count == 0)
+                return;
+
+            generatedLines.First().Alpha = 0.3f;
+            generatedLines.Last().Alpha = 0.3f;
+
+            AddRangeInternal(generatedLines);
         }
 
         public Vector2 GetSnappedPosition(Vector2 original)
diff --git a/osu.Game/Screens/OnlinePlay/FreeModSelectScreen.cs b/osu.Game/Screens/OnlinePlay/FreeModSelectScreen.cs
index c85a4fc38b..5a7a60b479 100644
--- a/osu.Game/Screens/OnlinePlay/FreeModSelectScreen.cs
+++ b/osu.Game/Screens/OnlinePlay/FreeModSelectScreen.cs
@@ -16,7 +16,7 @@ namespace osu.Game.Screens.OnlinePlay
         public new Func<Mod, bool> IsValidMod
         {
             get => base.IsValidMod;
-            set => base.IsValidMod = m => m.HasImplementation && m.UserPlayable && value.Invoke(m);
+            set => base.IsValidMod = m => m.UserPlayable && value.Invoke(m);
         }
 
         public FreeModSelectScreen()