diff --git a/qt/aqt/browser/browser.py b/qt/aqt/browser/browser.py
index 6d6c91b9b..e5eb6c912 100644
--- a/qt/aqt/browser/browser.py
+++ b/qt/aqt/browser/browser.py
@@ -18,7 +18,6 @@ from anki.utils import isMac
 from aqt import AnkiQt, gui_hooks
 from aqt.editor import Editor
 from aqt.exporting import ExportDialog
-from aqt.flags import load_flags
 from aqt.operations.card import set_card_deck, set_card_flag
 from aqt.operations.collection import redo, undo
 from aqt.operations.note import remove_notes
@@ -175,7 +174,7 @@ class Browser(QMainWindow):
         def set_flag_func(desired_flag: int) -> Callable:
             return lambda: self.set_flag_of_selected_cards(desired_flag)
 
-        for flag in load_flags(self.col):
+        for flag in self.mw.flags.all():
             qconnect(
                 getattr(self.form, flag.action).triggered, set_flag_func(flag.index)
             )
@@ -212,6 +211,7 @@ class Browser(QMainWindow):
         self._cleanup_preview()
         self.editor.cleanup()
         self.table.cleanup()
+        self.sidebar.cleanup()
         saveSplitter(self.form.splitter, "editor3")
         saveGeom(self, "editor")
         saveState(self, "editor")
@@ -702,13 +702,13 @@ class Browser(QMainWindow):
         flag = self.card and self.card.user_flag()
         flag = flag or 0
 
-        for f in load_flags(self.col):
+        for f in self.mw.flags.all():
             getattr(self.form, f.action).setChecked(flag == f.index)
 
         qtMenuShortcutWorkaround(self.form.menuFlag)
 
     def _update_flag_labels(self) -> None:
-        for flag in load_flags(self.col):
+        for flag in self.mw.flags.all():
             getattr(self.form, flag.action).setText(flag.label)
 
     def toggle_mark_of_selected_notes(self, checked: bool) -> None:
@@ -782,6 +782,7 @@ class Browser(QMainWindow):
         gui_hooks.backend_did_block.append(self.table.on_backend_did_block)
         gui_hooks.operation_did_execute.append(self.on_operation_did_execute)
         gui_hooks.focus_did_change.append(self.on_focus_change)
+        gui_hooks.flag_label_did_change.append(self._update_flag_labels)
 
     def teardownHooks(self) -> None:
         gui_hooks.undo_state_did_change.remove(self.on_undo_state_change)
@@ -789,6 +790,7 @@ class Browser(QMainWindow):
         gui_hooks.backend_did_block.remove(self.table.on_backend_will_block)
         gui_hooks.operation_did_execute.remove(self.on_operation_did_execute)
         gui_hooks.focus_did_change.remove(self.on_focus_change)
+        gui_hooks.flag_label_did_change.remove(self._update_flag_labels)
 
     # Undo
     ######################################################################
diff --git a/qt/aqt/browser/sidebar/tree.py b/qt/aqt/browser/sidebar/tree.py
index 52a7c97ed..157538633 100644
--- a/qt/aqt/browser/sidebar/tree.py
+++ b/qt/aqt/browser/sidebar/tree.py
@@ -26,7 +26,6 @@ from aqt.browser.sidebar.searchbar import SidebarSearchBar
 from aqt.browser.sidebar.toolbar import SidebarTool, SidebarToolbar
 from aqt.clayout import CardLayout
 from aqt.fields import FieldDialog
-from aqt.flags import load_flags
 from aqt.models import Models
 from aqt.operations import CollectionOp, QueryOp
 from aqt.operations.deck import (
@@ -109,6 +108,11 @@ class SidebarTreeView(QTreeView):
         self.toolbar = SidebarToolbar(self)
         self.searchBar = SidebarSearchBar(self)
 
+        gui_hooks.flag_label_did_change.append(self.refresh)
+
+    def cleanup(self) -> None:
+        gui_hooks.flag_label_did_change.remove(self.refresh)
+
     @property
     def tool(self) -> SidebarTool:
         return self._tool
@@ -677,7 +681,7 @@ class SidebarTreeView(QTreeView):
         )
         root.search_node = SearchNode(flag=SearchNode.FLAG_ANY)
 
-        for flag in load_flags(self.col):
+        for flag in self.mw.flags.all():
             root.add_child(
                 SidebarItem(
                     name=flag.label,
@@ -961,12 +965,8 @@ class SidebarTreeView(QTreeView):
     ###########################
 
     def rename_flag(self, item: SidebarItem, new_name: str) -> None:
-        labels = self.col.get_config("flagLabels", {})
-        labels[str(item.id)] = new_name
-        self.col.set_config("flagLabels", labels)
         item.name = new_name
-        self.browser._update_flag_labels()
-        self.refresh()
+        self.mw.flags.rename_flag(item.id, new_name)
 
     # Decks
     ###########################
diff --git a/qt/aqt/flags.py b/qt/aqt/flags.py
index 3d1780a13..d2767912c 100644
--- a/qt/aqt/flags.py
+++ b/qt/aqt/flags.py
@@ -3,11 +3,11 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import Dict, List, cast
+from typing import Dict, List, Optional, cast
 
-from anki import Collection
+import aqt
 from anki.collection import SearchNode
-from aqt import colors
+from aqt import colors, gui_hooks
 from aqt.theme import ColoredIcon
 from aqt.utils import tr
 
@@ -30,60 +30,82 @@ class Flag:
     action: str
 
 
-def load_flags(col: Collection) -> List[Flag]:
-    """Return a list of all flags, reloading labels from the config."""
+class FlagManager:
+    def __init__(self, mw: aqt.main.AnkiQt) -> None:
+        self.mw = mw
+        self._flags: Optional[List[Flag]] = None
 
-    labels = cast(Dict[str, str], col.get_config("flagLabels", {}))
-    icon = ColoredIcon(path=":/icons/flag.svg", color=colors.DISABLED)
+    def all(self) -> List[Flag]:
+        """Return a list of all flags."""
+        if self._flags is None:
+            self._load_flags()
+        return self._flags
 
-    return [
-        Flag(
-            1,
-            labels["1"] if "1" in labels else tr.actions_flag_red(),
-            icon.with_color(colors.FLAG1_FG),
-            SearchNode(flag=SearchNode.FLAG_RED),
-            "actionRed_Flag",
-        ),
-        Flag(
-            2,
-            labels["2"] if "2" in labels else tr.actions_flag_orange(),
-            icon.with_color(colors.FLAG2_FG),
-            SearchNode(flag=SearchNode.FLAG_ORANGE),
-            "actionOrange_Flag",
-        ),
-        Flag(
-            3,
-            labels["3"] if "3" in labels else tr.actions_flag_green(),
-            icon.with_color(colors.FLAG3_FG),
-            SearchNode(flag=SearchNode.FLAG_GREEN),
-            "actionGreen_Flag",
-        ),
-        Flag(
-            4,
-            labels["4"] if "4" in labels else tr.actions_flag_blue(),
-            icon.with_color(colors.FLAG4_FG),
-            SearchNode(flag=SearchNode.FLAG_BLUE),
-            "actionBlue_Flag",
-        ),
-        Flag(
-            5,
-            labels["5"] if "5" in labels else tr.actions_flag_pink(),
-            icon.with_color(colors.FLAG5_FG),
-            SearchNode(flag=SearchNode.FLAG_PINK),
-            "actionPink_Flag",
-        ),
-        Flag(
-            6,
-            labels["6"] if "6" in labels else tr.actions_flag_turquoise(),
-            icon.with_color(colors.FLAG6_FG),
-            SearchNode(flag=SearchNode.FLAG_TURQUOISE),
-            "actionTurquoise_Flag",
-        ),
-        Flag(
-            7,
-            labels["7"] if "7" in labels else tr.actions_flag_purple(),
-            icon.with_color(colors.FLAG7_FG),
-            SearchNode(flag=SearchNode.FLAG_PURPLE),
-            "actionPurple_Flag",
-        ),
-    ]
+    def get_flag(self, flag_index: int) -> Flag:
+        if not 1 <= flag_index <= len(self.all()):
+            raise Exception(f"Flag index out of range (1-{len(self.all())}).")
+        return self.all()[flag_index - 1]
+
+    def rename_flag(self, flag_index: int, new_name: str) -> None:
+        if new_name in ("", self.get_flag(flag_index).label):
+            return
+        labels = self.mw.col.get_config("flagLabels", {})
+        labels[str(flag_index)] = self.get_flag(flag_index).label = new_name
+        self.mw.col.set_config("flagLabels", labels)
+        gui_hooks.flag_label_did_change()
+
+    def _load_flags(self) -> None:
+        labels = cast(Dict[str, str], self.mw.col.get_config("flagLabels", {}))
+        icon = ColoredIcon(path=":/icons/flag.svg", color=colors.DISABLED)
+
+        self._flags = [
+            Flag(
+                1,
+                labels["1"] if "1" in labels else tr.actions_flag_red(),
+                icon.with_color(colors.FLAG1_FG),
+                SearchNode(flag=SearchNode.FLAG_RED),
+                "actionRed_Flag",
+            ),
+            Flag(
+                2,
+                labels["2"] if "2" in labels else tr.actions_flag_orange(),
+                icon.with_color(colors.FLAG2_FG),
+                SearchNode(flag=SearchNode.FLAG_ORANGE),
+                "actionOrange_Flag",
+            ),
+            Flag(
+                3,
+                labels["3"] if "3" in labels else tr.actions_flag_green(),
+                icon.with_color(colors.FLAG3_FG),
+                SearchNode(flag=SearchNode.FLAG_GREEN),
+                "actionGreen_Flag",
+            ),
+            Flag(
+                4,
+                labels["4"] if "4" in labels else tr.actions_flag_blue(),
+                icon.with_color(colors.FLAG4_FG),
+                SearchNode(flag=SearchNode.FLAG_BLUE),
+                "actionBlue_Flag",
+            ),
+            Flag(
+                5,
+                labels["5"] if "5" in labels else tr.actions_flag_pink(),
+                icon.with_color(colors.FLAG5_FG),
+                SearchNode(flag=SearchNode.FLAG_PINK),
+                "actionPink_Flag",
+            ),
+            Flag(
+                6,
+                labels["6"] if "6" in labels else tr.actions_flag_turquoise(),
+                icon.with_color(colors.FLAG6_FG),
+                SearchNode(flag=SearchNode.FLAG_TURQUOISE),
+                "actionTurquoise_Flag",
+            ),
+            Flag(
+                7,
+                labels["7"] if "7" in labels else tr.actions_flag_purple(),
+                icon.with_color(colors.FLAG7_FG),
+                SearchNode(flag=SearchNode.FLAG_PURPLE),
+                "actionPurple_Flag",
+            ),
+        ]
diff --git a/qt/aqt/main.py b/qt/aqt/main.py
index da4b9f69d..c224a18cb 100644
--- a/qt/aqt/main.py
+++ b/qt/aqt/main.py
@@ -48,6 +48,7 @@ from aqt import gui_hooks
 from aqt.addons import DownloadLogEntry, check_and_prompt_for_updates, show_log_to_user
 from aqt.dbcheck import check_db
 from aqt.emptycards import show_empty_cards
+from aqt.flags import FlagManager
 from aqt.legacy import install_pylib_legacy
 from aqt.mediacheck import check_media_db
 from aqt.mediasync import MediaSyncer
@@ -113,6 +114,7 @@ class AnkiQt(QMainWindow):
         self.col: Optional[Collection] = None
         self.taskman = TaskManager(self)
         self.media_syncer = MediaSyncer(self)
+        self.flags = FlagManager(self)
         aqt.mw = self
         self.app = app
         self.pm = profileManager
diff --git a/qt/aqt/reviewer.py b/qt/aqt/reviewer.py
index 326019f3a..fb46ab16c 100644
--- a/qt/aqt/reviewer.py
+++ b/qt/aqt/reviewer.py
@@ -25,7 +25,6 @@ from anki.utils import stripHTML
 from aqt import AnkiQt, gui_hooks
 from aqt.browser.card_info import CardInfoDialog
 from aqt.deckoptions import confirm_deck_then_display_options
-from aqt.flags import load_flags
 from aqt.operations.card import set_card_flag
 from aqt.operations.note import remove_notes
 from aqt.operations.scheduling import (
@@ -447,7 +446,7 @@ class Reviewer:
             (Qt.Key_F5, self.replayAudio),
             *(
                 (f"Ctrl+{flag.index}", self.set_flag_func(flag.index))
-                for flag in load_flags(self.mw.col)
+                for flag in self.mw.flags.all()
             ),
             ("*", self.toggle_mark_on_current_note),
             ("=", self.bury_current_note),
@@ -904,7 +903,7 @@ time = %(time)d;
                         self.set_flag_func(flag.index),
                         dict(checked=currentFlag == flag.index),
                     ]
-                    for flag in load_flags(self.mw.col)
+                    for flag in self.mw.flags.all()
                 ],
             ],
             [tr.studying_bury_card(), "-", self.bury_current_card],
diff --git a/qt/tools/genhooks_gui.py b/qt/tools/genhooks_gui.py
index 2fa4ed3a7..aebeb2587 100644
--- a/qt/tools/genhooks_gui.py
+++ b/qt/tools/genhooks_gui.py
@@ -946,6 +946,11 @@ gui_hooks.webview_did_inject_style_into_page.append(mytest)
         args=["menu: QMenu", "deck_id: int"],
         legacy_hook="showDeckOptions",
     ),
+    Hook(
+        name="flag_label_did_change",
+        args=[],
+        doc="Used to update the GUI when a new flag label is assigned.",
+    ),
 ]
 
 suffix = ""