diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9c50d97a..c93d899f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -43,6 +43,7 @@
 - Dev: Use `QMetaObject::invokeMethod` to run code on a specific thread. (#6203)
 - Dev: Added a `run-and-kill.sh` script to help debug crash-on-exit bugs. (#6188)
 - Dev: Refactored the `TimeoutStackStyle` enum into its own file. (#6216)
+- Dev: Refactored `Notebook`-related enums into their own file. (#6220)
 - Dev: Refactored event API initialization away from Application and into TwitchIrcServer. (#6198)
 - Dev: Updated GoogleTest to v1.17.0. (#6180)
 - Dev: Mini refactor of `TwitchAccount`. (#6182)
diff --git a/src/controllers/hotkeys/HotkeyController.cpp b/src/controllers/hotkeys/HotkeyController.cpp
index 48a57211..447c6b76 100644
--- a/src/controllers/hotkeys/HotkeyController.cpp
+++ b/src/controllers/hotkeys/HotkeyController.cpp
@@ -4,9 +4,12 @@
 #include "controllers/hotkeys/Hotkey.hpp"
 #include "controllers/hotkeys/HotkeyCategory.hpp"
 #include "controllers/hotkeys/HotkeyModel.hpp"
-#include "singletons/Settings.hpp"
+#include "util/RapidJsonSerializeQString.hpp"  // IWYU pragma: keep
 
+#include <pajlada/settings.hpp>
+#include <QMessageBox>
 #include <QShortcut>
+#include <QWidget>
 
 namespace {
 
diff --git a/src/controllers/plugins/PluginController.hpp b/src/controllers/plugins/PluginController.hpp
index 4c3a9aae..06fe5a1a 100644
--- a/src/controllers/plugins/PluginController.hpp
+++ b/src/controllers/plugins/PluginController.hpp
@@ -13,16 +13,15 @@
 #    include <QString>
 #    include <sol/forward.hpp>
 
-#    include <algorithm>
 #    include <map>
 #    include <memory>
 #    include <utility>
-#    include <vector>
 
 struct lua_State;
 
 namespace chatterino {
 
+class Settings;
 class Paths;
 
 class PluginController
diff --git a/src/singletons/Settings.hpp b/src/singletons/Settings.hpp
index 25e84c21..467b9b47 100644
--- a/src/singletons/Settings.hpp
+++ b/src/singletons/Settings.hpp
@@ -15,8 +15,8 @@
 #include "controllers/nicknames/Nickname.hpp"
 #include "controllers/sound/ISoundController.hpp"
 #include "singletons/Toasts.hpp"
-#include "util/RapidJsonSerializeQString.hpp"
-#include "widgets/Notebook.hpp"
+#include "util/RapidJsonSerializeQString.hpp"  // IWYU pragma: keep
+#include "widgets/NotebookEnums.hpp"
 
 #include <pajlada/settings/setting.hpp>
 #include <pajlada/settings/settinglistener.hpp>
diff --git a/src/util/StreamLink.cpp b/src/util/StreamLink.cpp
index 33e7b5a4..6e3edc15 100644
--- a/src/util/StreamLink.cpp
+++ b/src/util/StreamLink.cpp
@@ -5,8 +5,8 @@
 #include "common/Version.hpp"
 #include "singletons/Settings.hpp"
 #include "singletons/WindowManager.hpp"
-#include "util/Helpers.hpp"
 #include "widgets/dialogs/QualityPopup.hpp"
+#include "widgets/Notebook.hpp"
 #include "widgets/splits/Split.hpp"
 #include "widgets/Window.hpp"
 
diff --git a/src/widgets/Notebook.hpp b/src/widgets/Notebook.hpp
index 2f2a3c54..f5592d2e 100644
--- a/src/widgets/Notebook.hpp
+++ b/src/widgets/Notebook.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "widgets/BaseWidget.hpp"
+#include "widgets/NotebookEnums.hpp"
 
 #include <pajlada/signals/signal.hpp>
 #include <pajlada/signals/signalholder.hpp>
@@ -21,17 +22,6 @@ class NotebookTab;
 class SplitContainer;
 class Split;
 
-enum NotebookTabLocation { Top = 0, Left = 1, Right = 2, Bottom = 3 };
-
-// Controls the visibility of tabs in this notebook
-enum NotebookTabVisibility : int {
-    // Show all tabs
-    AllTabs = 0,
-
-    // Only show tabs containing splits that are live
-    LiveOnly = 1,
-};
-
 using TabVisibilityFilter = std::function<bool(const NotebookTab *)>;
 
 class Notebook : public BaseWidget
diff --git a/src/widgets/NotebookEnums.hpp b/src/widgets/NotebookEnums.hpp
new file mode 100644
index 00000000..16692738
--- /dev/null
+++ b/src/widgets/NotebookEnums.hpp
@@ -0,0 +1,16 @@
+#pragma once
+
+namespace chatterino {
+
+enum NotebookTabLocation { Top = 0, Left = 1, Right = 2, Bottom = 3 };
+
+// Controls the visibility of tabs in this notebook
+enum NotebookTabVisibility : int {
+    // Show all tabs
+    AllTabs = 0,
+
+    // Only show tabs containing splits that are live
+    LiveOnly = 1,
+};
+
+}  // namespace chatterino
diff --git a/src/widgets/OverlayWindow.cpp b/src/widgets/OverlayWindow.cpp
index 076776b8..ec54f0d2 100644
--- a/src/widgets/OverlayWindow.cpp
+++ b/src/widgets/OverlayWindow.cpp
@@ -20,6 +20,7 @@
 #include <QGraphicsEffect>
 #include <QGridLayout>
 #include <QKeySequence>
+#include <QMessageBox>
 #include <QSizeGrip>
 
 #ifdef Q_OS_WIN
diff --git a/src/widgets/dialogs/UserInfoPopup.cpp b/src/widgets/dialogs/UserInfoPopup.cpp
index 4e673fa0..dd1241bb 100644
--- a/src/widgets/dialogs/UserInfoPopup.cpp
+++ b/src/widgets/dialogs/UserInfoPopup.cpp
@@ -3,7 +3,6 @@
 #include "Application.hpp"
 #include "common/Channel.hpp"
 #include "common/Literals.hpp"
-#include "common/network/NetworkRequest.hpp"
 #include "common/QLogging.hpp"
 #include "controllers/accounts/AccountController.hpp"
 #include "controllers/commands/CommandController.hpp"
@@ -15,7 +14,6 @@
 #include "providers/IvrApi.hpp"
 #include "providers/pronouns/Pronouns.hpp"
 #include "providers/twitch/api/Helix.hpp"
-#include "providers/twitch/ChannelPointReward.hpp"
 #include "providers/twitch/TwitchAccount.hpp"
 #include "providers/twitch/TwitchChannel.hpp"
 #include "providers/twitch/TwitchIrcServer.hpp"
@@ -34,6 +32,7 @@
 #include "widgets/helper/InvisibleSizeGrip.hpp"
 #include "widgets/helper/Line.hpp"
 #include "widgets/Label.hpp"
+#include "widgets/Notebook.hpp"
 #include "widgets/Scrollbar.hpp"
 #include "widgets/splits/Split.hpp"
 #include "widgets/Window.hpp"
diff --git a/src/widgets/helper/ChannelView.cpp b/src/widgets/helper/ChannelView.cpp
index f11e9d5f..65a95a6a 100644
--- a/src/widgets/helper/ChannelView.cpp
+++ b/src/widgets/helper/ChannelView.cpp
@@ -41,6 +41,7 @@
 #include "widgets/helper/EffectLabel.hpp"
 #include "widgets/helper/ScrollbarHighlight.hpp"
 #include "widgets/helper/SearchPopup.hpp"
+#include "widgets/Notebook.hpp"
 #include "widgets/Scrollbar.hpp"
 #include "widgets/splits/Split.hpp"
 #include "widgets/splits/SplitInput.hpp"
diff --git a/src/widgets/settingspages/FiltersPage.cpp b/src/widgets/settingspages/FiltersPage.cpp
index 6789f4ea..67138b4c 100644
--- a/src/widgets/settingspages/FiltersPage.cpp
+++ b/src/widgets/settingspages/FiltersPage.cpp
@@ -10,6 +10,7 @@
 #include "widgets/helper/EditableModelView.hpp"
 
 #include <QHeaderView>
+#include <QMessageBox>
 #include <QTableView>
 
 namespace chatterino {
diff --git a/src/widgets/settingspages/GeneralPage.cpp b/src/widgets/settingspages/GeneralPage.cpp
index 4548f7a2..ab2b68f6 100644
--- a/src/widgets/settingspages/GeneralPage.cpp
+++ b/src/widgets/settingspages/GeneralPage.cpp
@@ -28,6 +28,7 @@
 #include <QFontDialog>
 #include <QFormLayout>
 #include <QLabel>
+#include <QMessageBox>
 #include <QScrollArea>
 
 namespace {