diff --git a/OpenRA.Game/Support/Log.cs b/OpenRA.Game/Support/Log.cs
index b8e254f0d9..2031163b61 100644
--- a/OpenRA.Game/Support/Log.cs
+++ b/OpenRA.Game/Support/Log.cs
@@ -171,6 +171,11 @@ namespace OpenRA
 			ChannelWriter.TryWrite(new ChannelData(channelName, value));
 		}
 
+		public static void Write(string channelName, Exception e)
+		{
+			ChannelWriter.TryWrite(new ChannelData(channelName, $"{e.Message}{Environment.NewLine}{e.StackTrace}"));
+		}
+
 		public static void Write(string channelName, string format, params object[] args)
 		{
             ChannelWriter.TryWrite(new ChannelData(channelName, format.F(args)));
diff --git a/OpenRA.Mods.Common/Traits/World/TimeLimitManager.cs b/OpenRA.Mods.Common/Traits/World/TimeLimitManager.cs
index 146e5bd819..c4dd6e691d 100644
--- a/OpenRA.Mods.Common/Traits/World/TimeLimitManager.cs
+++ b/OpenRA.Mods.Common/Traits/World/TimeLimitManager.cs
@@ -160,7 +160,7 @@ namespace OpenRA.Mods.Common.Traits
 				{
 					TextNotificationsManager.AddSystemLine(Notification.F(m, m > 1 ? "s" : null));
 
-					var faction = self.World.LocalPlayer == null ? null : self.World.LocalPlayer.Faction.InternalName;
+					var faction = self.World.LocalPlayer?.Faction.InternalName;
 					Game.Sound.PlayNotification(self.World.Map.Rules, self.World.LocalPlayer, "Speech", info.TimeLimitWarnings[m], faction);
 				}
 			}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/AssetBrowserLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/AssetBrowserLogic.cs
index 2d4e4d4ef6..78e343e493 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/AssetBrowserLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/AssetBrowserLogic.cs
@@ -97,7 +97,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var spriteWidget = panel.GetOrNull<SpriteWidget>("SPRITE");
 			if (spriteWidget != null)
 			{
-				spriteWidget.GetSprite = () => currentSprites != null ? currentSprites[currentFrame] : null;
+				spriteWidget.GetSprite = () => currentSprites?[currentFrame];
 				currentPalette = spriteWidget.Palette;
 				spriteScale = spriteWidget.Scale;
 				spriteWidget.GetPalette = () => currentPalette;
@@ -394,7 +394,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			if (string.IsNullOrWhiteSpace(filter))
 				return true;
 
-			if (filename.IndexOf(filter, StringComparison.OrdinalIgnoreCase) >= 0)
+			if (filename.Contains(filter, StringComparison.OrdinalIgnoreCase))
 				return true;
 
 			return false;
@@ -524,11 +524,12 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				else
 					return false;
 			}
-			catch (Exception ex)
+			catch (Exception exception)
 			{
 				isLoadError = true;
 				Log.AddChannel("assetbrowser", "assetbrowser.log");
-				Log.Write("assetbrowser", "Error reading {0}:{3} {1}{3}{2}", filename, ex.Message, ex.StackTrace, Environment.NewLine);
+				Log.Write("assetbrowser", $"Error reading {filename}");
+				Log.Write("assetbrowser", exception);
 
 				return false;
 			}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/CreditsLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/CreditsLogic.cs
index 625754875d..b849dc3a3f 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/CreditsLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/CreditsLogic.cs
@@ -90,7 +90,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			}
 		}
 
-		IEnumerable<string> ParseLines(Stream file)
+		static IEnumerable<string> ParseLines(Stream file)
 		{
 			return file.ReadAllLines().Select(l => l.Replace("\t", "    ").Replace("*", "\u2022")).ToList();
 		}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Editor/SaveMapLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Editor/SaveMapLogic.cs
index 261ed15e0c..1b17238a76 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Editor/SaveMapLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Editor/SaveMapLogic.cs
@@ -190,15 +190,15 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 
 					map.Save(package);
 
-					Console.WriteLine("Saved current map at {0}", combinedPath);
+					Console.WriteLine($"Saved current map at {combinedPath}");
 					Ui.CloseWindow();
 
 					onSave(map.Uid);
 				}
 				catch (Exception e)
 				{
-					Log.Write("debug", "Failed to save map at {0}: {1}", combinedPath, e.Message);
-					Log.Write("debug", "{0}", e.StackTrace);
+					Log.Write("debug", $"Failed to save map at {combinedPath}");
+					Log.Write("debug", e);
 
 					ConfirmationDialogs.ButtonPrompt(
 						title: "Failed to save map",
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Ingame/DebugMenuLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Ingame/DebugMenuLogic.cs
index d6495cf38d..bc9faf1bfa 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Ingame/DebugMenuLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Ingame/DebugMenuLogic.cs
@@ -153,7 +153,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			}
 		}
 
-		public void Order(World world, string order)
+		public static void Order(World world, string order)
 		{
 			world.IssueOrder(new Order(order, world.LocalPlayer.PlayerActor, false));
 		}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Ingame/GameInfoObjectivesLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Ingame/GameInfoObjectivesLogic.cs
index 97dfbf829d..cc8b55c719 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Ingame/GameInfoObjectivesLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Ingame/GameInfoObjectivesLogic.cs
@@ -58,7 +58,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			mo.ObjectiveAdded += redrawObjectives;
 		}
 
-		void PopulateObjectivesList(MissionObjectives mo, ScrollPanelWidget parent, ContainerWidget template)
+		static void PopulateObjectivesList(MissionObjectives mo, ScrollPanelWidget parent, ContainerWidget template)
 		{
 			parent.RemoveChildren();
 
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Ingame/ObserverStatsLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Ingame/ObserverStatsLogic.cs
index 6cfe1e9497..92ca68c7bd 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Ingame/ObserverStatsLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Ingame/ObserverStatsLogic.cs
@@ -469,7 +469,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			return template;
 		}
 
-		void SetupPlayerColor(Player player, ScrollItemWidget template, ColorBlockWidget colorBlockWidget, GradientColorBlockWidget gradientColorBlockWidget)
+		static void SetupPlayerColor(Player player, ScrollItemWidget template, ColorBlockWidget colorBlockWidget, GradientColorBlockWidget gradientColorBlockWidget)
 		{
 			var color = Color.FromArgb(128, player.Color.R, player.Color.G, player.Color.B);
 			var hoverColor = Color.FromArgb(192, player.Color.R, player.Color.G, player.Color.B);
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Ingame/ProductionTooltipLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Ingame/ProductionTooltipLogic.cs
index 6a12ccd9b2..e83517f806 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Ingame/ProductionTooltipLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Ingame/ProductionTooltipLogic.cs
@@ -48,7 +48,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var requiresFormat = requiresLabel.Text;
 
 			ActorInfo lastActor = null;
-			Hotkey lastHotkey = Hotkey.Invalid;
+			var lastHotkey = Hotkey.Invalid;
 			var lastPowerState = pm?.PowerState ?? PowerState.Normal;
 			var descLabelY = descLabel.Bounds.Y;
 			var descLabelPadding = descLabel.Bounds.Height;
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Ingame/SupportPowerTooltipLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Ingame/SupportPowerTooltipLogic.cs
index a95c069cc9..6feab45814 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Ingame/SupportPowerTooltipLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Ingame/SupportPowerTooltipLogic.cs
@@ -34,7 +34,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var timeOffset = timeLabel.Bounds.X;
 
 			SupportPowerInstance lastPower = null;
-			Hotkey lastHotkey = Hotkey.Invalid;
+			var lastHotkey = Hotkey.Invalid;
 			var lastRemainingSeconds = 0;
 
 			tooltipContainer.BeforeRender = () =>
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Installation/InstallFromDiscLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Installation/InstallFromDiscLogic.cs
index a5ba2e5b74..59581b5620 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Installation/InstallFromDiscLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Installation/InstallFromDiscLogic.cs
@@ -137,7 +137,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					var path = FindSourcePath(kv.Value, volumes);
 					if (path != null)
 					{
-						Log.Write("install", "Using installer `{0}: {1}` of type `{2}`:", kv.Key, kv.Value.Title, kv.Value.Type);
+						Log.Write("install", $"Using installer `{kv.Key}: {kv.Value.Title}` of type `{kv.Value.Type}`:");
 
 						var packages = content.Packages.Values
 							.Where(p => p.Sources.Contains(kv.Key) && !p.IsInstalled())
@@ -271,13 +271,13 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 									// Yaml path may be specified relative to a named directory (e.g. ^SupportDir) or the detected disc path
 									var sourcePath = i.Value.Value.StartsWith("^") ? Platform.ResolvePath(i.Value.Value) : Path.Combine(path, i.Value.Value);
 
-									Log.Write("debug", "Deleting {0}", sourcePath);
+									Log.Write("debug", $"Deleting {sourcePath}");
 									File.Delete(sourcePath);
 									break;
 								}
 
 							default:
-								Log.Write("debug", "Unknown installation command {0} - ignoring", i.Key);
+								Log.Write("debug", $"Unknown installation command {i.Key} - ignoring");
 								break;
 						}
 					}
@@ -499,7 +499,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			return null;
 		}
 
-		bool IsValidSourcePath(string path, ModContent.ModSource source)
+		static bool IsValidSourcePath(string path, ModContent.ModSource source)
 		{
 			try
 			{
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyLogic.cs
index 52f7f36730..1b8fc11a3a 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyLogic.cs
@@ -212,7 +212,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				slotsButton.IsVisible = () => panel != PanelType.Servers;
 				slotsButton.IsDisabled = () => configurationDisabled() || panel != PanelType.Players ||
 					(orderManager.LobbyInfo.Slots.Values.All(s => !s.AllowBots) &&
-					orderManager.LobbyInfo.Slots.Count(s => !s.Value.LockTeam && orderManager.LobbyInfo.ClientInSlot(s.Key) != null) == 0);
+					!orderManager.LobbyInfo.Slots.Any(s => !s.Value.LockTeam && orderManager.LobbyInfo.ClientInSlot(s.Key) != null));
 
 				slotsButton.OnMouseDown = _ =>
 				{
@@ -269,7 +269,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 						{
 							Title = $"{d} Teams",
 							IsSelected = () => false,
-							OnClick = () => orderManager.IssueOrder(Order.Command($"assignteams {d.ToString()}"))
+							OnClick = () => orderManager.IssueOrder(Order.Command($"assignteams {d}"))
 						}).ToList();
 
 						if (orderManager.LobbyInfo.Slots.Any(s => s.Value.AllowBots))
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyUtils.cs b/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyUtils.cs
index fad5751a65..163db23b5c 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyUtils.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyUtils.cs
@@ -45,7 +45,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				{
 					"Slot", new List<SlotDropDownOption>
 					{
-						new SlotDropDownOption("Open", "slot_open " + slot.PlayerReference, () => (!slot.Closed && client == null)),
+						new SlotDropDownOption("Open", "slot_open " + slot.PlayerReference, () => !slot.Closed && client == null),
 						new SlotDropDownOption("Closed", "slot_close " + slot.PlayerReference, () => slot.Closed)
 					}
 				}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Lobby/SpawnSelectorTooltipLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Lobby/SpawnSelectorTooltipLogic.cs
index 5d2f78842a..28b2621777 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Lobby/SpawnSelectorTooltipLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Lobby/SpawnSelectorTooltipLogic.cs
@@ -20,7 +20,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 		[ObjectCreator.UseCtor]
 		public SpawnSelectorTooltipLogic(Widget widget, TooltipContainerWidget tooltipContainer, MapPreviewWidget preview, bool showUnoccupiedSpawnpoints)
 		{
-			bool showTooltip = true;
+			var showTooltip = true;
 			widget.IsVisible = () => preview.TooltipSpawnIndex != -1 && showTooltip;
 			var label = widget.Get<LabelWidget>("LABEL");
 			var flag = widget.Get<ImageWidget>("FLAG");
diff --git a/OpenRA.Mods.Common/Widgets/Logic/MainMenuLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/MainMenuLogic.cs
index 13d3e165ae..a7d4244b79 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/MainMenuLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/MainMenuLogic.cs
@@ -346,7 +346,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			});
 		}
 
-		void LoadMapIntoEditor(string uid)
+		static void LoadMapIntoEditor(string uid)
 		{
 			Game.LoadEditor(uid);
 
diff --git a/OpenRA.Mods.Common/Widgets/Logic/MapChooserLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/MapChooserLogic.cs
index bba6279855..a1f51c852b 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/MapChooserLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/MapChooserLogic.cs
@@ -126,7 +126,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			SetupMapTab(MapClassification.User, filter, "USER_MAPS_TAB_BUTTON", "USER_MAPS_TAB", itemTemplate);
 			SetupMapTab(MapClassification.System, filter, "SYSTEM_MAPS_TAB_BUTTON", "SYSTEM_MAPS_TAB", itemTemplate);
 
-			if (initialMap == null && tabMaps.Keys.Contains(initialTab) && tabMaps[initialTab].Length > 0)
+			if (initialMap == null && tabMaps.ContainsKey(initialTab) && tabMaps[initialTab].Length > 0)
 			{
 				selectedUid = Game.ModData.MapCache.ChooseInitialMap(tabMaps[initialTab].Select(mp => mp.Uid).First(),
 					Game.CosmeticRandom);
@@ -178,8 +178,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				{
 					foreach (var category in map.Categories)
 					{
-						var count = 0;
-						categoryDict.TryGetValue(category, out count);
+						categoryDict.TryGetValue(category, out var count);
 						categoryDict[category] = count + 1;
 					}
 				}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/PlayerProfileLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/PlayerProfileLogic.cs
index bde099feae..b4a29ef839 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/PlayerProfileLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/PlayerProfileLogic.cs
@@ -211,9 +211,9 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 							{
 								var badges = Ui.LoadWidget("PLAYER_PROFILE_BADGES_INSERT", badgeContainer, new WidgetArgs()
 								{
-									{ "worldRenderer", worldRenderer },
-									{ "profile", profile },
-									{ "negotiateWidth", negotiateWidth }
+									{ nameof(worldRenderer), worldRenderer },
+									{ nameof(profile), profile },
+									{ nameof(negotiateWidth), negotiateWidth }
 								});
 
 								if (badges.Bounds.Height > 0)
@@ -236,7 +236,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				}
 				catch (Exception e)
 				{
-					Log.Write("debug", "Failed to parse player data result with exception: {0}", e);
+					Log.Write("debug", "Failed to parse player data result with exception");
+					Log.Write("debug", e);
 				}
 				finally
 				{
diff --git a/OpenRA.Mods.Common/Widgets/Logic/ReplayBrowserLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/ReplayBrowserLogic.cs
index 9141c6a130..3ce823fa0f 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/ReplayBrowserLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/ReplayBrowserLogic.cs
@@ -445,7 +445,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			};
 
 			var deleteAllButton = panel.Get<ButtonWidget>("MNG_DELALL_BUTTON");
-			deleteAllButton.IsDisabled = () => replayState.Count(kvp => kvp.Value.Visible) == 0;
+			deleteAllButton.IsDisabled = () => !replayState.Any(kvp => kvp.Value.Visible);
 			deleteAllButton.OnClick = () =>
 			{
 				var list = replayState.Where(kvp => kvp.Value.Visible).Select(kvp => kvp.Key).ToList();
@@ -511,7 +511,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			replayState.Remove(replay);
 		}
 
-		bool EvaluateReplayVisibility(ReplayMetadata replay)
+		static bool EvaluateReplayVisibility(ReplayMetadata replay)
 		{
 			// Game type
 			if ((filter.Type == GameType.Multiplayer && replay.GameInfo.IsSinglePlayer) || (filter.Type == GameType.Singleplayer && !replay.GameInfo.IsSinglePlayer))
@@ -675,7 +675,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			}
 			catch (Exception e)
 			{
-				Log.Write("debug", "Exception while parsing replay: {0}", e);
+				Log.Write("debug", $"Exception while parsing replay: {replay}");
+				Log.Write("debug", e);
 				SelectReplay(null);
 			}
 		}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/ServerListLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/ServerListLogic.cs
index f0401ec93d..b806552550 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/ServerListLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/ServerListLogic.cs
@@ -320,7 +320,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			RefreshServerList();
 		}
 
-		string PlayersLabel(GameServer game)
+		static string PlayersLabel(GameServer game)
 		{
 			return $"{(game.Players > 0 ? game.Players.ToString() : "No")} Player{(game.Players != 1 ? "s" : "")}{(game.Bots > 0 ? $", {game.Bots} Bot{(game.Bots != 1 ? "s" : "")}" : "")}{(game.Spectators > 0 ? $", {game.Spectators} Spectator{(game.Spectators != 1 ? "s" : "")}" : "")}";
 		}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Settings/InputSettingsLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Settings/InputSettingsLogic.cs
index ed8fe95106..14a225fc88 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Settings/InputSettingsLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Settings/InputSettingsLogic.cs
@@ -184,7 +184,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			dropdown.ShowDropDown("LABEL_DROPDOWN_TEMPLATE", 500, options.Keys, setupItem);
 		}
 
-		void MakeMouseFocusSettingsLive()
+		static void MakeMouseFocusSettingsLive()
 		{
 			var gameSettings = Game.Settings.Game;