diff --git a/quickshell/Common/Paths.qml b/quickshell/Common/Paths.qml
index 107e3a2d..7805a7f5 100644
--- a/quickshell/Common/Paths.qml
+++ b/quickshell/Common/Paths.qml
@@ -46,22 +46,20 @@ Singleton {
     }
 
     function moddedAppId(appId: string): string {
-        if (appId === "Spotify")
-            return "spotify";
-        if (appId === "beepertexts")
-            return "beeper";
-        if (appId === "home assistant desktop")
-            return "homeassistant-desktop";
-        if (appId.includes("com.transmissionbt.transmission")) {
-            if (DesktopEntries.heuristicLookup("transmission-gtk"))
-                return "transmission-gtk";
-            if (DesktopEntries.heuristicLookup("transmission"))
-                return "transmission";
-            return "transmission-gtk";
+        const subs = SettingsData.appIdSubstitutions || [];
+        for (let i = 0; i < subs.length; i++) {
+            const sub = subs[i];
+            if (sub.type === "exact" && appId === sub.pattern) {
+                return sub.replacement;
+            } else if (sub.type === "contains" && appId.includes(sub.pattern)) {
+                return sub.replacement;
+            } else if (sub.type === "regex") {
+                const match = appId.match(new RegExp(sub.pattern));
+                if (match) {
+                    return sub.replacement.replace(/\$(\d+)/g, (_, n) => match[n] || "");
+                }
+            }
         }
-        const steamMatch = appId.match(/^steam_app_(\d+)$/);
-        if (steamMatch)
-            return `steam_icon_${steamMatch[1]}`;
         return appId;
     }
 
@@ -71,7 +69,7 @@ Singleton {
         }
 
         const moddedId = moddedAppId(appId);
-        if (moddedId.startsWith("steam_icon_")) {
+        if (moddedId !== appId) {
             return Quickshell.iconPath(moddedId, true);
         }
 
diff --git a/quickshell/Common/SettingsData.qml b/quickshell/Common/SettingsData.qml
index 321fdc64..5a4afec9 100644
--- a/quickshell/Common/SettingsData.qml
+++ b/quickshell/Common/SettingsData.qml
@@ -221,6 +221,7 @@ Singleton {
     property bool keyboardLayoutNameCompactMode: false
     property bool runningAppsCurrentWorkspace: false
     property bool runningAppsGroupByApp: false
+    property var appIdSubstitutions: []
     property string centeringMode: "index"
     property string clockDateFormat: ""
     property string lockDateFormat: ""
@@ -1842,6 +1843,40 @@ Singleton {
         return workspaceNameIcons[workspaceName] || null;
     }
 
+    function addAppIdSubstitution(pattern, replacement, type) {
+        var subs = JSON.parse(JSON.stringify(appIdSubstitutions));
+        subs.push({ pattern: pattern, replacement: replacement, type: type });
+        appIdSubstitutions = subs;
+        saveSettings();
+    }
+
+    function updateAppIdSubstitution(index, pattern, replacement, type) {
+        var subs = JSON.parse(JSON.stringify(appIdSubstitutions));
+        if (index < 0 || index >= subs.length)
+            return;
+        subs[index] = { pattern: pattern, replacement: replacement, type: type };
+        appIdSubstitutions = subs;
+        saveSettings();
+    }
+
+    function removeAppIdSubstitution(index) {
+        var subs = JSON.parse(JSON.stringify(appIdSubstitutions));
+        if (index < 0 || index >= subs.length)
+            return;
+        subs.splice(index, 1);
+        appIdSubstitutions = subs;
+        saveSettings();
+    }
+
+    function getDefaultAppIdSubstitutions() {
+        return Spec.SPEC.appIdSubstitutions.def;
+    }
+
+    function resetAppIdSubstitutions() {
+        appIdSubstitutions = JSON.parse(JSON.stringify(Spec.SPEC.appIdSubstitutions.def));
+        saveSettings();
+    }
+
     function getRegistryThemeVariant(themeId, defaultVariant) {
         var stored = registryThemeVariants[themeId];
         if (typeof stored === "string")
diff --git a/quickshell/Common/settings/SettingsSpec.js b/quickshell/Common/settings/SettingsSpec.js
index 3b2fd9e8..341bbecf 100644
--- a/quickshell/Common/settings/SettingsSpec.js
+++ b/quickshell/Common/settings/SettingsSpec.js
@@ -115,6 +115,13 @@ var SPEC = {
     keyboardLayoutNameCompactMode: { def: false },
     runningAppsCurrentWorkspace: { def: false },
     runningAppsGroupByApp: { def: false },
+    appIdSubstitutions: { def: [
+        { pattern: "Spotify", replacement: "spotify", type: "exact" },
+        { pattern: "beepertexts", replacement: "beeper", type: "exact" },
+        { pattern: "home assistant desktop", replacement: "homeassistant-desktop", type: "exact" },
+        { pattern: "com.transmissionbt.transmission", replacement: "transmission-gtk", type: "contains" },
+        { pattern: "^steam_app_(\\d+)$", replacement: "steam_icon_$1", type: "regex" }
+    ]},
     centeringMode: { def: "index" },
     clockDateFormat: { def: "" },
     lockDateFormat: { def: "" },
diff --git a/quickshell/Modules/DankBar/Widgets/FocusedApp.qml b/quickshell/Modules/DankBar/Widgets/FocusedApp.qml
index 58bc7868..0cd641e0 100644
--- a/quickshell/Modules/DankBar/Widgets/FocusedApp.qml
+++ b/quickshell/Modules/DankBar/Widgets/FocusedApp.qml
@@ -56,6 +56,13 @@ BasePill {
         }
     }
 
+    Connections {
+        target: SettingsData
+        function onAppIdSubstitutionsChanged() {
+            root.updateDesktopEntry();
+        }
+    }
+
     function updateDesktopEntry() {
         if (activeWindow && activeWindow.appId) {
             const moddedId = Paths.moddedAppId(activeWindow.appId);
diff --git a/quickshell/Modules/DankBar/Widgets/RunningApps.qml b/quickshell/Modules/DankBar/Widgets/RunningApps.qml
index a5f61126..926f2c5d 100644
--- a/quickshell/Modules/DankBar/Widgets/RunningApps.qml
+++ b/quickshell/Modules/DankBar/Widgets/RunningApps.qml
@@ -69,6 +69,7 @@ Item {
 
     property int _desktopEntriesUpdateTrigger: 0
     property int _toplevelsUpdateTrigger: 0
+    property int _appIdSubstitutionsTrigger: 0
 
     readonly property var sortedToplevels: {
         _toplevelsUpdateTrigger;
@@ -95,6 +96,13 @@ Item {
             _desktopEntriesUpdateTrigger++;
         }
     }
+
+    Connections {
+        target: SettingsData
+        function onAppIdSubstitutionsChanged() {
+            _appIdSubstitutionsTrigger++;
+        }
+    }
     readonly property var groupedWindows: {
         if (!SettingsData.runningAppsGroupByApp) {
             return [];
@@ -364,6 +372,7 @@ Item {
                             height: Theme.barIconSize(root.barThickness)
                             source: {
                                 root._desktopEntriesUpdateTrigger;
+                                root._appIdSubstitutionsTrigger;
                                 if (!appId)
                                     return "";
                                 const moddedId = Paths.moddedAppId(appId);
@@ -596,6 +605,7 @@ Item {
                             height: Theme.barIconSize(root.barThickness)
                             source: {
                                 root._desktopEntriesUpdateTrigger;
+                                root._appIdSubstitutionsTrigger;
                                 if (!appId)
                                     return "";
                                 const moddedId = Paths.moddedAppId(appId);
diff --git a/quickshell/Modules/DankBar/Widgets/WorkspaceSwitcher.qml b/quickshell/Modules/DankBar/Widgets/WorkspaceSwitcher.qml
index ac5388c1..1cfdc362 100644
--- a/quickshell/Modules/DankBar/Widgets/WorkspaceSwitcher.qml
+++ b/quickshell/Modules/DankBar/Widgets/WorkspaceSwitcher.qml
@@ -265,7 +265,8 @@ Item {
 
             if (!byApp[key]) {
                 const isQuickshell = keyBase === "org.quickshell";
-                const desktopEntry = DesktopEntries.heuristicLookup(keyBase);
+                const moddedId = Paths.moddedAppId(keyBase);
+                const desktopEntry = DesktopEntries.heuristicLookup(moddedId);
                 const icon = Paths.getAppIcon(keyBase, desktopEntry);
                 byApp[key] = {
                     "type": "icon",
@@ -1367,6 +1368,9 @@ Item {
                     function onWorkspaceNameIconsChanged() {
                         delegateRoot.updateAllData();
                     }
+                    function onAppIdSubstitutionsChanged() {
+                        delegateRoot.updateAllData();
+                    }
                 }
                 Connections {
                     target: DwlService
diff --git a/quickshell/Modules/Dock/DockAppButton.qml b/quickshell/Modules/Dock/DockAppButton.qml
index c5744527..8c0197e6 100644
--- a/quickshell/Modules/Dock/DockAppButton.qml
+++ b/quickshell/Modules/Dock/DockAppButton.qml
@@ -49,6 +49,13 @@ Item {
             updateDesktopEntry();
         }
     }
+
+    Connections {
+        target: SettingsData
+        function onAppIdSubstitutionsChanged() {
+            updateDesktopEntry();
+        }
+    }
     property bool isWindowFocused: {
         if (!appData) {
             return false;
diff --git a/quickshell/Modules/Settings/RunningAppsTab.qml b/quickshell/Modules/Settings/RunningAppsTab.qml
index 49f7c5a2..636f8740 100644
--- a/quickshell/Modules/Settings/RunningAppsTab.qml
+++ b/quickshell/Modules/Settings/RunningAppsTab.qml
@@ -32,6 +32,159 @@ Item {
                     onToggled: checked => SettingsData.set("runningAppsCurrentWorkspace", checked)
                 }
             }
+
+            SettingsCard {
+                width: parent.width
+                iconName: "find_replace"
+                title: I18n.tr("App ID Substitutions")
+                settingKey: "appIdSubstitutions"
+                tags: ["app", "icon", "substitution", "replacement", "pattern", "window", "class", "regex"]
+
+                headerActions: [
+                    DankActionButton {
+                        buttonSize: 36
+                        iconName: "restart_alt"
+                        iconSize: 20
+                        visible: JSON.stringify(SettingsData.appIdSubstitutions) !== JSON.stringify(SettingsData.getDefaultAppIdSubstitutions())
+                        backgroundColor: Theme.surfaceContainer
+                        iconColor: Theme.surfaceVariantText
+                        onClicked: SettingsData.resetAppIdSubstitutions()
+                    },
+                    DankActionButton {
+                        buttonSize: 36
+                        iconName: "add"
+                        iconSize: 20
+                        backgroundColor: Theme.surfaceContainer
+                        iconColor: Theme.primary
+                        onClicked: SettingsData.addAppIdSubstitution("", "", "exact")
+                    }
+                ]
+
+                Column {
+                    width: parent.width
+                    spacing: Theme.spacingS
+
+                    StyledText {
+                        text: I18n.tr("Map window class names to icon names for proper icon display")
+                        font.pixelSize: Theme.fontSizeSmall
+                        color: Theme.surfaceVariantText
+                        wrapMode: Text.WordWrap
+                        width: parent.width
+                        bottomPadding: Theme.spacingS
+                    }
+
+                    Repeater {
+                        model: SettingsData.appIdSubstitutions
+
+                        delegate: Rectangle {
+                            id: subItem
+                            width: parent.width
+                            height: subColumn.implicitHeight + Theme.spacingM
+                            radius: Theme.cornerRadius
+                            color: Theme.withAlpha(Theme.surfaceContainer, 0.5)
+
+                            Column {
+                                id: subColumn
+                                anchors.fill: parent
+                                anchors.margins: Theme.spacingS
+                                spacing: Theme.spacingS
+
+                                Row {
+                                    width: parent.width
+                                    spacing: Theme.spacingS
+
+                                    Column {
+                                        width: (parent.width - deleteBtn.width - Theme.spacingS) / 2
+                                        spacing: 2
+
+                                        StyledText {
+                                            text: I18n.tr("Pattern")
+                                            font.pixelSize: Theme.fontSizeSmall - 1
+                                            color: Theme.surfaceVariantText
+                                        }
+
+                                        DankTextField {
+                                            id: patternField
+                                            width: parent.width
+                                            text: modelData.pattern
+                                            font.pixelSize: Theme.fontSizeSmall
+                                            onEditingFinished: SettingsData.updateAppIdSubstitution(index, text, replacementField.text, modelData.type)
+                                        }
+                                    }
+
+                                    Column {
+                                        width: (parent.width - deleteBtn.width - Theme.spacingS) / 2
+                                        spacing: 2
+
+                                        StyledText {
+                                            text: I18n.tr("Replacement")
+                                            font.pixelSize: Theme.fontSizeSmall - 1
+                                            color: Theme.surfaceVariantText
+                                        }
+
+                                        DankTextField {
+                                            id: replacementField
+                                            width: parent.width
+                                            text: modelData.replacement
+                                            font.pixelSize: Theme.fontSizeSmall
+                                            onEditingFinished: SettingsData.updateAppIdSubstitution(index, patternField.text, text, modelData.type)
+                                        }
+                                    }
+
+                                    Item {
+                                        id: deleteBtn
+                                        width: 32
+                                        height: 40
+                                        anchors.verticalCenter: parent.verticalCenter
+
+                                        Rectangle {
+                                            anchors.fill: parent
+                                            radius: Theme.cornerRadius
+                                            color: deleteArea.containsMouse ? Theme.withAlpha(Theme.error, 0.2) : "transparent"
+                                        }
+
+                                        DankIcon {
+                                            anchors.centerIn: parent
+                                            name: "delete"
+                                            size: 18
+                                            color: deleteArea.containsMouse ? Theme.error : Theme.surfaceVariantText
+                                        }
+
+                                        MouseArea {
+                                            id: deleteArea
+                                            anchors.fill: parent
+                                            hoverEnabled: true
+                                            cursorShape: Qt.PointingHandCursor
+                                            onClicked: SettingsData.removeAppIdSubstitution(index)
+                                        }
+                                    }
+                                }
+
+                                Column {
+                                    width: 120
+                                    spacing: 2
+
+                                    StyledText {
+                                        text: I18n.tr("Type")
+                                        font.pixelSize: Theme.fontSizeSmall - 1
+                                        color: Theme.surfaceVariantText
+                                    }
+
+                                    DankDropdown {
+                                        width: parent.width
+                                        compactMode: true
+                                        dropdownWidth: 120
+                                        currentValue: modelData.type
+                                        options: ["exact", "contains", "regex"]
+                                        onValueChanged: value => SettingsData.updateAppIdSubstitution(index, modelData.pattern, modelData.replacement, value)
+                                    }
+                                }
+                            }
+                        }
+                    }
+
+                }
+            }
         }
     }
 }
diff --git a/quickshell/Modules/Settings/Widgets/SettingsCard.qml b/quickshell/Modules/Settings/Widgets/SettingsCard.qml
index 4d64119b..c4d1c58f 100644
--- a/quickshell/Modules/Settings/Widgets/SettingsCard.qml
+++ b/quickshell/Modules/Settings/Widgets/SettingsCard.qml
@@ -142,7 +142,7 @@ StyledRect {
 
             Row {
                 id: headerActionsRow
-                anchors.right: caretIcon.left
+                anchors.right: root.collapsible ? caretIcon.left : parent.right
                 anchors.rightMargin: root.collapsible ? Theme.spacingS : 0
                 anchors.verticalCenter: parent.verticalCenter
                 spacing: Theme.spacingXS
@@ -172,6 +172,7 @@ StyledRect {
             }
 
             MouseArea {
+                visible: root.collapsible
                 anchors.left: caretIcon.left
                 anchors.right: parent.right
                 anchors.top: parent.top
diff --git a/quickshell/Modules/WorkspaceOverlays/OverviewWindow.qml b/quickshell/Modules/WorkspaceOverlays/OverviewWindow.qml
index 643207c9..43899714 100644
--- a/quickshell/Modules/WorkspaceOverlays/OverviewWindow.qml
+++ b/quickshell/Modules/WorkspaceOverlays/OverviewWindow.qml
@@ -33,8 +33,8 @@ Item {
 
     property var iconToWindowRatio: 0.25
     property var iconToWindowRatioCompact: 0.45
-    property var entry: DesktopEntries.heuristicLookup(windowData?.class)
-    property var iconPath: Quickshell.iconPath(entry?.icon ?? windowData?.class ?? "application-x-executable", "image-missing")
+    property var entry: DesktopEntries.heuristicLookup(Paths.moddedAppId(windowData?.class ?? ""))
+    property var iconPath: Paths.getAppIcon(windowData?.class ?? "", entry) || Quickshell.iconPath("application-x-executable", "image-missing")
     property bool compactMode: Theme.fontSizeSmall * 4 > targetWindowHeight || Theme.fontSizeSmall * 4 > targetWindowWidth
 
     x: initX
diff --git a/quickshell/translations/settings_search_index.json b/quickshell/translations/settings_search_index.json
index 9f682b8b..3b88bc83 100644
--- a/quickshell/translations/settings_search_index.json
+++ b/quickshell/translations/settings_search_index.json
@@ -3153,33 +3153,6 @@
     "icon": "lock",
     "description": "If the field is hidden, it will appear as soon as a key is pressed."
   },
-  {
-    "section": "lockScreenNotificationMode",
-    "label": "Notification Display",
-    "tabIndex": 11,
-    "category": "Lock Screen",
-    "keywords": [
-      "alert",
-      "control",
-      "display",
-      "information",
-      "lock",
-      "lockscreen",
-      "login",
-      "monitor",
-      "notif",
-      "notification",
-      "notifications",
-      "output",
-      "password",
-      "privacy",
-      "screen",
-      "security",
-      "shown",
-      "what"
-    ],
-    "description": "Control what notification information is shown on the lock screen"
-  },
   {
     "section": "lockScreenShowPasswordField",
     "label": "Show Password Field",
@@ -3915,6 +3888,35 @@
     ],
     "description": "Timeout for normal priority notifications"
   },
+  {
+    "section": "lockScreenNotificationMode",
+    "label": "Notification Display",
+    "tabIndex": 17,
+    "category": "Notifications",
+    "keywords": [
+      "alert",
+      "alerts",
+      "control",
+      "display",
+      "information",
+      "lock",
+      "lockscreen",
+      "login",
+      "messages",
+      "monitor",
+      "notif",
+      "notification",
+      "notifications",
+      "output",
+      "privacy",
+      "screen",
+      "security",
+      "shown",
+      "toast",
+      "what"
+    ],
+    "description": "Control what notification information is shown on the lock screen"
+  },
   {
     "section": "notificationOverlayEnabled",
     "label": "Notification Overlay",
@@ -4036,6 +4038,29 @@
     "icon": "tune",
     "description": "Choose where on-screen displays appear on screen"
   },
+  {
+    "section": "appIdSubstitutions",
+    "label": "App ID Substitutions",
+    "tabIndex": 19,
+    "category": "Running Apps",
+    "keywords": [
+      "active",
+      "app",
+      "apps",
+      "class",
+      "icon",
+      "pattern",
+      "regex",
+      "replacement",
+      "running",
+      "substitution",
+      "substitutions",
+      "tasks",
+      "window",
+      "windows"
+    ],
+    "icon": "find_replace"
+  },
   {
     "section": "runningApps",
     "label": "Running Apps Settings",