diff --git a/logger_prefs.json b/logger_prefs.json
new file mode 100644
index 0000000..d910040
--- /dev/null
+++ b/logger_prefs.json
@@ -0,0 +1,3 @@
+{
+    "saved_levels": {}
+}
\ No newline at end of file
diff --git a/settings.json b/settings.json
index a62124e..adca711 100644
--- a/settings.json
+++ b/settings.json
@@ -3,7 +3,7 @@
         "scan_limit": 60,
         "max_range": 100,
         "geometry": "1599x1089+501+84",
-        "last_selected_scenario": "scenario3",
+        "last_selected_scenario": null,
         "connection": {
             "target": {
                 "type": "sfp",
diff --git a/target_simulator/__main__.py b/target_simulator/__main__.py
index 65864f7..b8233a8 100644
--- a/target_simulator/__main__.py
+++ b/target_simulator/__main__.py
@@ -16,9 +16,14 @@ if project_root not in sys.path:
     sys.path.insert(0, project_root)
 
 from target_simulator.gui.main_view import MainView
-from utils.logger import setup_basic_logging, get_logger, add_tkinter_handler
+from target_simulator.utils.logger import (
+    setup_basic_logging,
+    get_logger,
+    add_tkinter_handler,
+    apply_saved_logger_levels,
+)
 
-from config import LOGGING_CONFIG
+from target_simulator.config import LOGGING_CONFIG
 
 
 def main():
@@ -32,6 +37,13 @@ def main():
     # Setup the global logging system, connecting it to the GUI's main loop
     setup_basic_logging(app, LOGGING_CONFIG)
 
+    # Apply any saved logger levels so preferences take effect even if the
+    # LoggerPanel is never opened.
+    try:
+        apply_saved_logger_levels()
+    except Exception:
+        pass
+
     # Now that the logging system is active, add the handler for the GUI widget
     add_tkinter_handler(app.log_text_widget, LOGGING_CONFIG)
 
diff --git a/target_simulator/gui/logger_panel.py b/target_simulator/gui/logger_panel.py
index d902dbf..dabf756 100644
--- a/target_simulator/gui/logger_panel.py
+++ b/target_simulator/gui/logger_panel.py
@@ -6,6 +6,9 @@ import tkinter as tk
 from tkinter import ttk, messagebox
 import logging
 from typing import List
+from target_simulator.utils.config_manager import ConfigManager
+import os
+import json
 
 LEVELS = [
     ("NOTSET", logging.NOTSET),
@@ -29,17 +32,44 @@ class LoggerPanel(tk.Toplevel):
 
         self.logger_names = []  # type: List[str]
 
+        # Config manager for persistence
+        try:
+            self._cfg = ConfigManager()
+        except Exception:
+            self._cfg = None
+
         self._create_widgets()
         self._populate_logger_list()
 
+        # Load persisted selections and levels
+        try:
+            self._load_persisted()
+        except Exception:
+            pass
+
     def _create_widgets(self):
         top = ttk.Frame(self)
         top.pack(fill=tk.BOTH, expand=True, padx=8, pady=8)
 
-        # Left: list of logger names
+        # Left: filter + list of logger names
         left = ttk.Frame(top)
         left.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)
 
+        ttk.Label(left, text="Filter:").pack(anchor=tk.W)
+        self.filter_var = tk.StringVar(value="")
+        self.filter_entry = ttk.Entry(left, textvariable=self.filter_var)
+        self.filter_entry.pack(fill=tk.X, padx=(0, 6), pady=(2, 4))
+        # Call _on_filter_change on text changes
+        try:
+            # Python 3.6+ trace_add preferred
+            self.filter_var.trace_add("write", lambda *args: self._on_filter_change())
+        except Exception:
+            # Fallback for older trace
+            try:
+                self.filter_var.trace("w", lambda *args: self._on_filter_change())
+            except Exception:
+                pass
+
         ttk.Label(left, text="Available loggers:").pack(anchor=tk.W)
         self.logger_listbox = tk.Listbox(left, exportselection=False)
         self.logger_listbox.pack(fill=tk.BOTH, expand=True, padx=(0, 6), pady=(4, 0))
@@ -61,6 +91,7 @@ class LoggerPanel(tk.Toplevel):
 
         ttk.Button(right, text="Apply", command=self._apply_level).pack(fill=tk.X, pady=(6, 4))
         ttk.Button(right, text="Reset to NOTSET", command=self._reset_level).pack(fill=tk.X)
+        ttk.Button(right, text="Restore defaults", command=self._restore_defaults).pack(fill=tk.X, pady=(6, 0))
 
         ttk.Separator(self).pack(fill=tk.X, pady=6)
 
@@ -74,6 +105,7 @@ class LoggerPanel(tk.Toplevel):
         ttk.Button(bottom, text="Open", command=self._open_named_logger).pack(side=tk.LEFT)
 
         ttk.Button(self, text="Refresh", command=self._populate_logger_list).pack(side=tk.RIGHT, padx=8, pady=(0, 8))
+        ttk.Button(self, text="Export", command=self._export_prefs).pack(side=tk.RIGHT, padx=(0,8), pady=(0,8))
         ttk.Button(self, text="Close", command=self._on_close).pack(side=tk.RIGHT, pady=(0, 8))
 
     def _gather_logger_names(self) -> List[str]:
@@ -95,12 +127,71 @@ class LoggerPanel(tk.Toplevel):
         names = sorted(set(names))
         return names
 
-    def _populate_logger_list(self):
+    def _refresh_list(self):
+        """Refresh listbox contents applying current filter against _all_logger_names."""
+        try:
+            filt = (self.filter_var.get() or "").strip().lower()
+        except Exception:
+            filt = ""
+
+        # Build filtered list
+        if hasattr(self, "_all_logger_names") and self._all_logger_names:
+            source = self._all_logger_names
+        else:
+            source = self.logger_names
+
+        if filt:
+            filtered = [n for n in source if filt in n.lower()]
+        else:
+            filtered = list(source)
+
+        # Remember current selection name to try to preserve it
+        try:
+            sel_idx = self.logger_listbox.curselection()
+            sel_name = self.logger_names[sel_idx[0]] if sel_idx else None
+        except Exception:
+            sel_name = None
+
+        # Update listbox
         self.logger_listbox.delete(0, tk.END)
-        self.logger_names = self._gather_logger_names()
+        self.logger_names = sorted(filtered)
         for n in self.logger_names:
             self.logger_listbox.insert(tk.END, n)
 
+        # Restore selection if still present
+        if sel_name and sel_name in self.logger_names:
+            idx = self.logger_names.index(sel_name)
+            self.logger_listbox.select_set(idx)
+            self.logger_listbox.see(idx)
+            self._on_select_logger()
+
+    def _on_filter_change(self, *args):
+        """Callback for filter text changes; refresh the list."""
+        try:
+            self._refresh_list()
+        except Exception:
+            pass
+
+    def _populate_logger_list(self):
+        self.logger_listbox.delete(0, tk.END)
+        # Gather and cache the full set of logger names, then refresh list
+        self._all_logger_names = self._gather_logger_names()
+        # Apply filter and populate listbox
+        self._refresh_list()
+        # If user previously selected a logger, select it
+        try:
+            if self._cfg:
+                gen = self._cfg.get_general_settings()
+                lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
+                last = lp.get("last_selected")
+                if last and last in self.logger_names:
+                    idx = self.logger_names.index(last)
+                    self.logger_listbox.select_set(idx)
+                    self.logger_listbox.see(idx)
+                    self._on_select_logger()
+        except Exception:
+            pass
+
     def _on_select_logger(self, event=None):
         sel = self.logger_listbox.curselection()
         if not sel:
@@ -122,7 +213,41 @@ class LoggerPanel(tk.Toplevel):
         lvl_name = self.level_var.get()
         lvl = next((v for n, v in LEVELS if n == lvl_name), logging.INFO)
         logging.getLogger(name).setLevel(lvl)
-        messagebox.showinfo("Logger level set", f"Logger '{name}' set to {lvl_name}.")
+        # Persist this selection into dedicated logger_prefs.json (single source of truth)
+        try:
+            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
+            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
+            # Read existing prefs
+            try:
+                with open(prefs_path, 'r', encoding='utf-8') as f:
+                    prefs = json.load(f) if f else {}
+                    if not isinstance(prefs, dict):
+                        prefs = {}
+            except Exception:
+                prefs = {}
+
+            saved = prefs.get('saved_levels', {}) if isinstance(prefs.get('saved_levels', {}), dict) else {}
+            saved[name] = lvl_name
+            prefs['saved_levels'] = saved
+            prefs['last_selected'] = name
+            with open(prefs_path, 'w', encoding='utf-8') as f:
+                json.dump(prefs, f, indent=4)
+        except Exception:
+            pass
+
+        # Post a status message to the application log instead of a modal dialog
+        try:
+            # Show a transient status in the main UI if available
+            parent = getattr(self, 'master', None)
+            if parent and hasattr(parent, 'show_status_message'):
+                parent.show_status_message(f"Logger '{name}' set to {lvl_name} (saved)")
+            else:
+                logging.getLogger(__name__).info("Logger '%s' set to %s (persisted)", name, lvl_name)
+        except Exception:
+            try:
+                messagebox.showinfo("Logger level set", f"Logger '{name}' set to {lvl_name}.")
+            except Exception:
+                pass
 
     def _reset_level(self):
         name = self.selected_name_var.get()
@@ -131,7 +256,41 @@ class LoggerPanel(tk.Toplevel):
             return
         logging.getLogger(name).setLevel(logging.NOTSET)
         self.level_var.set('NOTSET')
-        messagebox.showinfo("Logger reset", f"Logger '{name}' reset to NOTSET.")
+        # Remove persisted level for this logger from logger_prefs.json
+        try:
+            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
+            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
+            try:
+                with open(prefs_path, 'r', encoding='utf-8') as f:
+                    prefs = json.load(f) if f else {}
+                    if not isinstance(prefs, dict):
+                        prefs = {}
+            except Exception:
+                prefs = {}
+
+            saved = prefs.get('saved_levels', {}) if isinstance(prefs.get('saved_levels', {}), dict) else {}
+            if name in saved:
+                del saved[name]
+                prefs['saved_levels'] = saved
+                # if last_selected pointed to this logger, remove it
+                if prefs.get('last_selected') == name:
+                    prefs.pop('last_selected', None)
+                with open(prefs_path, 'w', encoding='utf-8') as f:
+                    json.dump(prefs, f, indent=4)
+        except Exception:
+            pass
+
+        try:
+            parent = getattr(self, 'master', None)
+            if parent and hasattr(parent, 'show_status_message'):
+                parent.show_status_message(f"Logger '{name}' reset to NOTSET (saved)")
+            else:
+                logging.getLogger(__name__).info("Logger '%s' reset to NOTSET (persisted)", name)
+        except Exception:
+            try:
+                messagebox.showinfo("Logger reset", f"Logger '{name}' reset to NOTSET.")
+            except Exception:
+                pass
 
     def _open_named_logger(self):
         name = self.new_logger_var.get().strip()
@@ -139,17 +298,116 @@ class LoggerPanel(tk.Toplevel):
             return
         # If exists in list, select it
         try:
-            idx = self.logger_names.index(name)
+            idx = self._all_logger_names.index(name)
         except ValueError:
             # Add to list
-            self.logger_names.append(name)
-            self.logger_names.sort()
+            # Add to cached master list and refresh
+            if not hasattr(self, "_all_logger_names"):
+                self._all_logger_names = []
+            if name not in self._all_logger_names:
+                self._all_logger_names.append(name)
+                self._all_logger_names.sort()
             self._populate_logger_list()
             idx = self.logger_names.index(name)
         self.logger_listbox.select_clear(0, tk.END)
         self.logger_listbox.select_set(idx)
         self.logger_listbox.see(idx)
         self._on_select_logger()
+        # Persist last selected into logger_prefs.json
+        try:
+            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
+            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
+            try:
+                with open(prefs_path, 'r', encoding='utf-8') as f:
+                    prefs = json.load(f) if f else {}
+                    if not isinstance(prefs, dict):
+                        prefs = {}
+            except Exception:
+                prefs = {}
+            prefs['last_selected'] = name
+            with open(prefs_path, 'w', encoding='utf-8') as f:
+                json.dump(prefs, f, indent=4)
+        except Exception:
+            pass
+        try:
+            parent = getattr(self, 'master', None)
+            if parent and hasattr(parent, 'show_status_message'):
+                parent.show_status_message(f"Selected logger: {name}")
+        except Exception:
+            pass
+
+    def _restore_defaults(self):
+        """Clear all saved logger preferences and reset those loggers to NOTSET."""
+        if not self._cfg:
+            try:
+                messagebox.showinfo("Restore defaults", "Could not access settings to restore defaults.")
+            except Exception:
+                pass
+            return
+
+        try:
+            gen = self._cfg.get_general_settings()
+            lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
+            saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
+            # Reset each saved logger to NOTSET
+            for name in list(saved.keys()):
+                try:
+                    logging.getLogger(name).setLevel(logging.NOTSET)
+                except Exception:
+                    pass
+            # Remove saved_levels
+            # Clear dedicated prefs file instead of touching settings.json
+            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
+            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
+            try:
+                with open(prefs_path, 'w', encoding='utf-8') as f:
+                    json.dump({"saved_levels": {}}, f, indent=4)
+            except Exception:
+                # fallback: attempt to remove the file
+                try:
+                    if os.path.exists(prefs_path):
+                        os.remove(prefs_path)
+                except Exception:
+                    pass
+            logging.getLogger(__name__).info("LoggerPanel: restored defaults and cleared saved preferences")
+            # Refresh the list and selection
+            self._populate_logger_list()
+        except Exception:
+            try:
+                messagebox.showinfo("Restore defaults", "Failed to restore defaults.")
+            except Exception:
+                pass
+
+    def _export_prefs(self):
+        """Export saved logger preferences to a separate JSON file for inspection."""
+        if not self._cfg:
+            try:
+                messagebox.showinfo("Export prefs", "Settings manager not available; cannot export.")
+            except Exception:
+                pass
+            return
+
+        try:
+            gen = self._cfg.get_general_settings()
+            lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
+            saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
+            # Determine export path next to settings.json
+            cfg_path = getattr(self._cfg, 'filepath', None)
+            export_dir = os.path.dirname(cfg_path) if cfg_path else os.getcwd()
+            export_path = os.path.join(export_dir, "logger_prefs.json")
+            with open(export_path, 'w', encoding='utf-8') as f:
+                json.dump({"saved_levels": saved}, f, indent=4)
+
+            parent = getattr(self, 'master', None)
+            if parent and hasattr(parent, 'show_status_message'):
+                parent.show_status_message(f"Exported logger prefs to {export_path}")
+            else:
+                logging.getLogger(__name__).info("Exported logger prefs to %s", export_path)
+        except Exception:
+            try:
+                messagebox.showinfo("Export prefs", "Failed to export logger preferences.")
+            except Exception:
+                pass
 
     def _on_close(self):
         try:
@@ -157,3 +415,37 @@ class LoggerPanel(tk.Toplevel):
         except Exception:
             pass
         self.destroy()
+
+    def _load_persisted(self):
+        """Load persisted logger panel settings and apply saved levels."""
+        # Prefer reading the dedicated prefs file
+        cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
+        prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
+        saved = {}
+        try:
+            if os.path.exists(prefs_path):
+                with open(prefs_path, 'r', encoding='utf-8') as f:
+                    jp = json.load(f)
+                    if isinstance(jp, dict):
+                        saved = jp.get('saved_levels', {}) or {}
+                        last = jp.get('last_selected')
+                        if last:
+                            # store last_selected in prefs for later UI use
+                            pass
+            else:
+                # Fallback to settings.json
+                if self._cfg:
+                    gen = self._cfg.get_general_settings()
+                    lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
+                    saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
+        except Exception:
+            saved = {}
+
+        # Apply saved levels to loggers
+        for name, lvl_name in (saved or {}).items():
+            try:
+                lvl = logging.getLevelName(lvl_name)
+                if isinstance(lvl, int):
+                    logging.getLogger(name).setLevel(lvl)
+            except Exception:
+                pass
diff --git a/target_simulator/gui/main_view.py b/target_simulator/gui/main_view.py
index 99ff0f9..f4237e1 100644
--- a/target_simulator/gui/main_view.py
+++ b/target_simulator/gui/main_view.py
@@ -87,6 +87,8 @@ class MainView(tk.Tk):
         self._create_menubar()
         self._create_main_layout()
         self._create_statusbar()
+        # Id for scheduled status clear; used by show_status_message
+        self._status_after_id = None
 
         # --- Post-UI Initialization ---
         self._initialize_communicators()
@@ -383,6 +385,36 @@ class MainView(tk.Tk):
             side=tk.LEFT, fill=tk.X, expand=True, padx=5
         )
 
+    def show_status_message(self, text: str, timeout_ms: int = 3000):
+        """Show a transient status message in the main status bar.
+
+        If another message is scheduled to clear, cancel it and schedule the
+        new message to be cleared after timeout_ms.
+        """
+        try:
+            # Cancel previous scheduled clear if any
+            try:
+                if self._status_after_id is not None:
+                    self.after_cancel(self._status_after_id)
+            except Exception:
+                pass
+            # Set message
+            self.status_var.set(text)
+            # Schedule clear back to Ready
+            def _clear():
+                try:
+                    self.status_var.set("Ready")
+                except Exception:
+                    pass
+
+            self._status_after_id = self.after(timeout_ms, _clear)
+        except Exception:
+            # As a fallback, log the status
+            try:
+                self.logger.info(text)
+            except Exception:
+                pass
+
     def _draw_status_indicator(self, canvas, color):
         canvas.delete("all")
         canvas.create_oval(2, 2, 14, 14, fill=color, outline="black")
@@ -1116,14 +1148,44 @@ class MainView(tk.Tk):
         if self.is_simulation_running.get():
             self._on_stop_simulation()
 
-        settings_to_save = {
-            "scan_limit": self.scan_limit,
-            "max_range": self.max_range,
-            "geometry": self.winfo_geometry(),
-            "last_selected_scenario": self.current_scenario_name,
-        }
-        self.config_manager.save_general_settings(settings_to_save)
-        self.config_manager.save_connection_settings(self.connection_config)
+        # Merge current runtime general settings with any existing saved
+        # settings so we don't clobber unrelated keys (e.g., logger_panel).
+        try:
+            existing = self.config_manager.get_general_settings() or {}
+        except Exception:
+            existing = {}
+
+        settings_to_save = dict(existing)
+        settings_to_save.update(
+            {
+                "scan_limit": self.scan_limit,
+                "max_range": self.max_range,
+                "geometry": self.winfo_geometry(),
+                "last_selected_scenario": self.current_scenario_name,
+            }
+        )
+
+        # Save merged general settings and connection settings separately
+        try:
+            self.config_manager.save_general_settings(settings_to_save)
+        except Exception:
+            # Fallback: try to write the minimal dict if merge/save fails
+            try:
+                self.config_manager.save_general_settings(
+                    {
+                        "scan_limit": self.scan_limit,
+                        "max_range": self.max_range,
+                        "geometry": self.winfo_geometry(),
+                        "last_selected_scenario": self.current_scenario_name,
+                    }
+                )
+            except Exception:
+                pass
+
+        try:
+            self.config_manager.save_connection_settings(self.connection_config)
+        except Exception:
+            pass
 
         if self.target_communicator:
             if hasattr(self.target_communicator, 'remove_connection_state_callback'):
diff --git a/target_simulator/utils/config_manager.py b/target_simulator/utils/config_manager.py
index 98a9508..cb33b58 100644
--- a/target_simulator/utils/config_manager.py
+++ b/target_simulator/utils/config_manager.py
@@ -149,7 +149,21 @@ class ConfigManager:
 
     def save_general_settings(self, data: Dict[str, Any]):
         """Saves the general settings."""
-        self._settings["general"] = data
+        # Merge incoming general settings with existing ones to avoid
+        # overwriting unrelated keys (for example: logger_panel saved prefs).
+        existing = self._settings.get("general", {}) if isinstance(self._settings, dict) else {}
+        try:
+            # Shallow merge: if a key contains a dict, update its contents
+            for k, v in (data or {}).items():
+                if isinstance(v, dict) and k in existing and isinstance(existing.get(k), dict):
+                    existing[k].update(v)
+                else:
+                    existing[k] = v
+        except Exception:
+            # Fallback: replace entirely if merge fails
+            existing = data
+
+        self._settings["general"] = existing
         self._save_settings()
 
     def get_scenario_names(self) -> List[str]:
diff --git a/target_simulator/utils/logger.py b/target_simulator/utils/logger.py
index 7f53b25..d0739fb 100644
--- a/target_simulator/utils/logger.py
+++ b/target_simulator/utils/logger.py
@@ -7,6 +7,9 @@ from queue import Queue, Empty as QueueEmpty
 from typing import Optional, Dict, Any
 from contextlib import contextmanager
 from logging import Logger
+from target_simulator.utils.config_manager import ConfigManager
+import os
+import json
 
 # Module-level logger for utils.logging helpers
 logger = logging.getLogger(__name__)
@@ -210,3 +213,50 @@ def shutdown_logging_system():
     # Final flush of the queue
     _process_global_log_queue()
     logging.shutdown()
+
+
+def apply_saved_logger_levels():
+    """Apply saved logger levels from ConfigManager at startup.
+
+    Reads `general.logger_panel.saved_levels` from settings.json and sets
+    each configured logger to the saved level name.
+    """
+    try:
+        cfg = ConfigManager()
+    except Exception:
+        return
+
+    try:
+        # Prefer a dedicated logger_prefs.json next to the main settings file
+        prefs_path = None
+        cfg_path = getattr(cfg, "filepath", None)
+        if cfg_path:
+            prefs_path = os.path.join(os.path.dirname(cfg_path), "logger_prefs.json")
+
+        saved = {}
+        if prefs_path and os.path.exists(prefs_path):
+            try:
+                with open(prefs_path, "r", encoding="utf-8") as f:
+                    jp = json.load(f)
+                    if isinstance(jp, dict):
+                        saved = jp.get("saved_levels", {}) or {}
+            except Exception:
+                saved = {}
+        else:
+            # Fallback to settings.json general.logger_panel
+            try:
+                gen = cfg.get_general_settings()
+                lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
+                saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
+            except Exception:
+                saved = {}
+
+        for name, lvl_name in (saved or {}).items():
+            try:
+                lvl_val = logging.getLevelName(lvl_name)
+                if isinstance(lvl_val, int):
+                    logging.getLogger(name).setLevel(lvl_val)
+            except Exception:
+                pass
+    except Exception:
+        pass
diff --git a/tests/test_logger_persistence.py b/tests/test_logger_persistence.py
new file mode 100644
index 0000000..4ca89c8
--- /dev/null
+++ b/tests/test_logger_persistence.py
@@ -0,0 +1,117 @@
+import os
+import json
+import logging
+
+from target_simulator.utils.config_manager import ConfigManager
+from target_simulator.utils.logger import apply_saved_logger_levels
+
+
+def _prefs_path(cfg: ConfigManager) -> str:
+    return os.path.join(os.path.dirname(cfg.filepath), "logger_prefs.json")
+
+
+def test_apply_saved_logger_levels_from_prefs_file(tmp_path):
+    cfg = ConfigManager()
+    settings_path = cfg.filepath
+    prefs = {"saved_levels": {"test.logger.persistence": "DEBUG"}}
+    prefs_path = _prefs_path(cfg)
+
+    # Backup existing settings.json and prefs if present
+    if os.path.exists(settings_path):
+        with open(settings_path, "r", encoding="utf-8") as f:
+            orig_settings = f.read()
+    else:
+        orig_settings = None
+
+    if os.path.exists(prefs_path):
+        with open(prefs_path, "r", encoding="utf-8") as f:
+            orig_prefs = f.read()
+    else:
+        orig_prefs = None
+
+    try:
+        # Ensure the logger starts at INFO
+        lg = logging.getLogger("test.logger.persistence")
+        lg.setLevel(logging.INFO)
+
+        # Write prefs file and apply
+        with open(prefs_path, "w", encoding="utf-8") as f:
+            json.dump(prefs, f, indent=2)
+
+        apply_saved_logger_levels()
+
+        # After applying, the logger should be DEBUG
+        assert logging.getLogger("test.logger.persistence").level == logging.DEBUG
+
+        # Now change prefs to WARNING and re-apply
+        prefs["saved_levels"]["test.logger.persistence"] = "WARNING"
+        with open(prefs_path, "w", encoding="utf-8") as f:
+            json.dump(prefs, f, indent=2)
+
+        apply_saved_logger_levels()
+        assert logging.getLogger("test.logger.persistence").level == logging.WARNING
+
+    finally:
+        # Restore original files
+        if orig_settings is not None:
+            with open(settings_path, "w", encoding="utf-8") as f:
+                f.write(orig_settings)
+        if orig_prefs is not None:
+            with open(prefs_path, "w", encoding="utf-8") as f:
+                f.write(orig_prefs)
+        else:
+            try:
+                if os.path.exists(prefs_path):
+                    os.remove(prefs_path)
+            except Exception:
+                pass
+
+
+def test_apply_saved_logger_levels_fallback_to_settings(tmp_path):
+    cfg = ConfigManager()
+    settings_path = cfg.filepath
+    prefs_path = _prefs_path(cfg)
+
+    # Backup
+    if os.path.exists(settings_path):
+        with open(settings_path, "r", encoding="utf-8") as f:
+            orig_settings = f.read()
+    else:
+        orig_settings = None
+    if os.path.exists(prefs_path):
+        with open(prefs_path, "r", encoding="utf-8") as f:
+            orig_prefs = f.read()
+    else:
+        orig_prefs = None
+
+    try:
+        # Remove prefs file to force fallback
+        if os.path.exists(prefs_path):
+            os.remove(prefs_path)
+
+        # Prepare settings.json general.logger_panel
+        cfg_gen = cfg.get_general_settings() or {}
+        cfg_gen["logger_panel"] = {"saved_levels": {"test.logger.fallback": "ERROR"}}
+        cfg.save_general_settings(cfg_gen)
+
+        # Ensure logger initial level is lower
+        logging.getLogger("test.logger.fallback").setLevel(logging.DEBUG)
+
+        apply_saved_logger_levels()
+
+        assert logging.getLogger("test.logger.fallback").level == logging.ERROR
+
+    finally:
+        # Restore originals
+        if orig_settings is not None:
+            with open(settings_path, "w", encoding="utf-8") as f:
+                f.write(orig_settings)
+        if orig_prefs is not None:
+            with open(prefs_path, "w", encoding="utf-8") as f:
+                f.write(orig_prefs)
+        else:
+            try:
+                if os.path.exists(prefs_path):
+                    os.remove(prefs_path)
+            except Exception:
+                pass