diff --git a/src/password_manager/manager.py b/src/password_manager/manager.py
index af2bb9e..3868068 100644
--- a/src/password_manager/manager.py
+++ b/src/password_manager/manager.py
@@ -18,9 +18,9 @@ import hashlib
 from typing import Optional
 import shutil
 import time
-import select
 import builtins
 from termcolor import colored
+from utils.input_utils import timed_input
 
 from password_manager.encryption import EncryptionManager
 from password_manager.entry_management import EntryManager
@@ -1285,14 +1285,12 @@ class PasswordManager:
                             sys.stdout.write(f"\r{bar} {remaining:2d}s")
                             sys.stdout.flush()
                             try:
-                                if (
-                                    sys.stdin
-                                    in select.select([sys.stdin], [], [], 1)[0]
-                                ):
-                                    user_input = sys.stdin.readline().strip().lower()
-                                    if user_input == "b":
-                                        exit_loop = True
-                                        break
+                                user_input = timed_input("", 1)
+                                if user_input.strip().lower() == "b":
+                                    exit_loop = True
+                                    break
+                            except TimeoutError:
+                                pass
                             except KeyboardInterrupt:
                                 exit_loop = True
                                 print()
@@ -2009,10 +2007,11 @@ class PasswordManager:
                             print(f"[{idx}] {label}: {code} {bar} {remaining:2d}s")
                 sys.stdout.flush()
                 try:
-                    if sys.stdin in select.select([sys.stdin], [], [], 1)[0]:
-                        user_input = sys.stdin.readline().strip().lower()
-                        if user_input == "b":
-                            break
+                    user_input = timed_input("", 1)
+                    if user_input.strip().lower() == "b":
+                        break
+                except TimeoutError:
+                    pass
                 except KeyboardInterrupt:
                     print()
                     break
diff --git a/src/password_manager/password_generation.py b/src/password_manager/password_generation.py
index 5b80e37..8d95e0d 100644
--- a/src/password_manager/password_generation.py
+++ b/src/password_manager/password_generation.py
@@ -30,6 +30,15 @@ from cryptography.hazmat.primitives.asymmetric import ed25519
 from cryptography.hazmat.backends import default_backend
 from bip_utils import Bip39SeedGenerator
 
+# Ensure the ``imghdr`` module is available for ``pgpy`` on Python 3.13+
+try:  # pragma: no cover - only executed on Python >= 3.13
+    import imghdr  # type: ignore
+except ModuleNotFoundError:  # pragma: no cover - fallback for removed module
+    from utils import imghdr_stub as imghdr  # type: ignore
+    import sys
+
+    sys.modules.setdefault("imghdr", imghdr)
+
 from local_bip85.bip85 import BIP85
 
 from constants import DEFAULT_PASSWORD_LENGTH, MIN_PASSWORD_LENGTH, MAX_PASSWORD_LENGTH
diff --git a/src/tests/test_manager_display_totp_codes.py b/src/tests/test_manager_display_totp_codes.py
index c9f12a7..b2773e0 100644
--- a/src/tests/test_manager_display_totp_codes.py
+++ b/src/tests/test_manager_display_totp_codes.py
@@ -50,7 +50,7 @@ def test_handle_display_totp_codes(monkeypatch, capsys):
 
         # interrupt the loop after first iteration
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
+            "password_manager.manager.timed_input",
             lambda *a, **k: (_ for _ in ()).throw(KeyboardInterrupt()),
         )
 
@@ -91,7 +91,7 @@ def test_display_totp_codes_excludes_blacklisted(monkeypatch, capsys):
         )
 
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
+            "password_manager.manager.timed_input",
             lambda *a, **k: (_ for _ in ()).throw(KeyboardInterrupt()),
         )
 
diff --git a/src/tests/test_manager_list_entries.py b/src/tests/test_manager_list_entries.py
index b780360..5d7dd3a 100644
--- a/src/tests/test_manager_list_entries.py
+++ b/src/tests/test_manager_list_entries.py
@@ -69,10 +69,9 @@ def test_list_entries_show_details(monkeypatch, capsys):
             pm.entry_manager, "get_totp_time_remaining", lambda *a, **k: 1
         )
         monkeypatch.setattr("password_manager.manager.time.sleep", lambda *a, **k: None)
-        monkeypatch.setattr(sys.stdin, "readline", lambda *a, **k: "b\n")
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
-            lambda *a, **k: ([sys.stdin], [], []),
+            "password_manager.manager.timed_input",
+            lambda *a, **k: "b",
         )
 
         inputs = iter(["1", "0"])
diff --git a/src/tests/test_manager_retrieve_totp.py b/src/tests/test_manager_retrieve_totp.py
index e127773..b67fe27 100644
--- a/src/tests/test_manager_retrieve_totp.py
+++ b/src/tests/test_manager_retrieve_totp.py
@@ -49,10 +49,9 @@ def test_handle_retrieve_totp_entry(monkeypatch, capsys):
             pm.entry_manager, "get_totp_time_remaining", lambda *a, **k: 1
         )
         monkeypatch.setattr("password_manager.manager.time.sleep", lambda *a, **k: None)
-        monkeypatch.setattr(sys.stdin, "readline", lambda *a, **k: "b\n")
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
-            lambda *a, **k: ([sys.stdin], [], []),
+            "password_manager.manager.timed_input",
+            lambda *a, **k: "b",
         )
 
         pm.handle_retrieve_entry()
diff --git a/src/tests/test_secret_mode.py b/src/tests/test_secret_mode.py
index 193094f..7087396 100644
--- a/src/tests/test_secret_mode.py
+++ b/src/tests/test_secret_mode.py
@@ -66,7 +66,7 @@ def test_totp_display_secret_mode(monkeypatch, capsys):
             pm.entry_manager, "get_totp_time_remaining", lambda *a, **k: 30
         )
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
+            "password_manager.manager.timed_input",
             lambda *a, **k: (_ for _ in ()).throw(KeyboardInterrupt()),
         )
         called = []
@@ -115,7 +115,7 @@ def test_totp_display_no_secret_mode(monkeypatch, capsys):
             pm.entry_manager, "get_totp_time_remaining", lambda *a, **k: 30
         )
         monkeypatch.setattr(
-            "password_manager.manager.select.select",
+            "password_manager.manager.timed_input",
             lambda *a, **k: (_ for _ in ()).throw(KeyboardInterrupt()),
         )
         called = []
diff --git a/src/utils/imghdr_stub.py b/src/utils/imghdr_stub.py
new file mode 100644
index 0000000..326824f
--- /dev/null
+++ b/src/utils/imghdr_stub.py
@@ -0,0 +1,216 @@
+"""Compat module providing :mod:`imghdr` for Python 3.13+.
+
+This is a copy of Python 3.12's :mod:`imghdr` module which was removed in
+Python 3.13. It is used by the ``pgpy`` dependency when deriving PGP keys.
+"""
+
+from __future__ import annotations
+
+from os import PathLike
+import warnings
+
+__all__ = ["what"]
+
+warnings._deprecated(__name__, remove=(3, 13))
+
+# -------------------------
+# Recognize image headers
+# -------------------------
+
+
+def what(file, h=None):
+    """Return the type of image contained in a file or byte stream."""
+    f = None
+    try:
+        if h is None:
+            if isinstance(file, (str, PathLike)):
+                f = open(file, "rb")
+                h = f.read(32)
+            else:
+                location = file.tell()
+                h = file.read(32)
+                file.seek(location)
+        for tf in tests:
+            res = tf(h, f)
+            if res:
+                return res
+    finally:
+        if f:
+            f.close()
+    return None
+
+
+# ---------------------------------
+# Subroutines per image file type
+# ---------------------------------
+
+tests: list = []
+
+
+def test_jpeg(h, f):
+    """Test for JPEG data with JFIF or Exif markers; and raw JPEG."""
+    if h[6:10] in (b"JFIF", b"Exif"):
+        return "jpeg"
+    elif h[:4] == b"\xff\xd8\xff\xdb":
+        return "jpeg"
+
+
+tests.append(test_jpeg)
+
+
+def test_png(h, f):
+    """Verify if the image is a PNG."""
+    if h.startswith(b"\211PNG\r\n\032\n"):
+        return "png"
+
+
+tests.append(test_png)
+
+
+def test_gif(h, f):
+    """Verify if the image is a GIF ('87 or '89 variants)."""
+    if h[:6] in (b"GIF87a", b"GIF89a"):
+        return "gif"
+
+
+tests.append(test_gif)
+
+
+def test_tiff(h, f):
+    """Verify if the image is a TIFF (Motorola or Intel)."""
+    if h[:2] in (b"MM", b"II"):
+        return "tiff"
+
+
+tests.append(test_tiff)
+
+
+def test_rgb(h, f):
+    """Test for the SGI image library."""
+    if h.startswith(b"\001\332"):
+        return "rgb"
+
+
+tests.append(test_rgb)
+
+
+def test_pbm(h, f):
+    """Verify if the image is a PBM."""
+    if len(h) >= 3 and h[0] == ord(b"P") and h[1] in b"14" and h[2] in b" \t\n\r":
+        return "pbm"
+
+
+tests.append(test_pbm)
+
+
+def test_pgm(h, f):
+    """Verify if the image is a PGM."""
+    if len(h) >= 3 and h[0] == ord(b"P") and h[1] in b"25" and h[2] in b" \t\n\r":
+        return "pgm"
+
+
+tests.append(test_pgm)
+
+
+def test_ppm(h, f):
+    """Verify if the image is a PPM."""
+    if len(h) >= 3 and h[0] == ord(b"P") and h[1] in b"36" and h[2] in b" \t\n\r":
+        return "ppm"
+
+
+tests.append(test_ppm)
+
+
+def test_rast(h, f):
+    """Test for the Sun raster file."""
+    if h.startswith(b"\x59\xa6\x6a\x95"):
+        return "rast"
+
+
+tests.append(test_rast)
+
+
+def test_xbm(h, f):
+    """Verify if the image is a X bitmap."""
+    if h.startswith(b"#define "):
+        return "xbm"
+
+
+tests.append(test_xbm)
+
+
+def test_bmp(h, f):
+    """Verify if the image is a BMP file."""
+    if h.startswith(b"BM"):
+        return "bmp"
+
+
+tests.append(test_bmp)
+
+
+def test_webp(h, f):
+    """Verify if the image is a WebP."""
+    if h.startswith(b"RIFF") and h[8:12] == b"WEBP":
+        return "webp"
+
+
+tests.append(test_webp)
+
+
+def test_exr(h, f):
+    """Verify if the image is an OpenEXR file."""
+    if h.startswith(b"\x76\x2f\x31\x01"):
+        return "exr"
+
+
+tests.append(test_exr)
+
+
+# --------------------
+# Small test program
+# --------------------
+
+
+def test():  # pragma: no cover - only used for manual testing
+    import sys
+
+    recursive = 0
+    if sys.argv[1:] and sys.argv[1] == "-r":
+        del sys.argv[1:2]
+        recursive = 1
+    try:
+        if sys.argv[1:]:
+            testall(sys.argv[1:], recursive, 1)
+        else:
+            testall(["."], recursive, 1)
+    except KeyboardInterrupt:
+        sys.stderr.write("\n[Interrupted]\n")
+        sys.exit(1)
+
+
+def testall(list, recursive, toplevel):  # pragma: no cover - only for manual use
+    import sys
+    import os
+
+    for filename in list:
+        if os.path.isdir(filename):
+            print(filename + "/:", end=" ")
+            if recursive or toplevel:
+                print("recursing down:")
+                import glob
+
+                names = glob.glob(os.path.join(glob.escape(filename), "*"))
+                testall(names, recursive, 0)
+            else:
+                print("*** directory (use -r) ***")
+        else:
+            print(filename + ":", end=" ")
+            sys.stdout.flush()
+            try:
+                print(what(filename))
+            except OSError:
+                print("*** not found ***")
+
+
+if __name__ == "__main__":  # pragma: no cover - manual run
+    test()