diff --git a/.ci/requirements-mypy.txt b/.ci/requirements-mypy.txt
index a9c18ae2b..44b5badab 100644
--- a/.ci/requirements-mypy.txt
+++ b/.ci/requirements-mypy.txt
@@ -1,4 +1,4 @@
-mypy==1.16.0
+mypy==1.16.1
 IceSpringPySideStubs-PyQt6
 IceSpringPySideStubs-PySide6
 ipython
diff --git a/.github/workflows/wheels-dependencies.sh b/.github/workflows/wheels-dependencies.sh
index b46811f5a..996d32bc2 100755
--- a/.github/workflows/wheels-dependencies.sh
+++ b/.github/workflows/wheels-dependencies.sh
@@ -39,7 +39,7 @@ ARCHIVE_SDIR=pillow-depends-main
 # Package versions for fresh source builds
 FREETYPE_VERSION=2.13.3
 HARFBUZZ_VERSION=11.2.1
-LIBPNG_VERSION=1.6.48
+LIBPNG_VERSION=1.6.49
 JPEGTURBO_VERSION=3.1.1
 OPENJPEG_VERSION=2.5.3
 XZ_VERSION=5.8.1
diff --git a/Tests/test_file_blp.py b/Tests/test_file_blp.py
index 9f50df22d..5f6b263a1 100644
--- a/Tests/test_file_blp.py
+++ b/Tests/test_file_blp.py
@@ -7,9 +7,8 @@ import pytest
 from PIL import BlpImagePlugin, Image
 
 from .helper import (
-    assert_image_equal,
     assert_image_equal_tofile,
-    assert_image_similar,
+    assert_image_similar_tofile,
     hopper,
 )
 
@@ -52,18 +51,16 @@ def test_save(tmp_path: Path) -> None:
         im = hopper("P")
         im.save(f, blp_version=version)
 
-        with Image.open(f) as reloaded:
-            assert_image_equal(im.convert("RGB"), reloaded)
+        assert_image_equal_tofile(im.convert("RGB"), f)
 
         with Image.open("Tests/images/transparent.png") as im:
             f = tmp_path / "temp.blp"
             im.convert("P").save(f, blp_version=version)
 
-            with Image.open(f) as reloaded:
-                assert_image_similar(im, reloaded, 8)
+            assert_image_similar_tofile(im, f, 8)
 
     im = hopper()
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="Unsupported BLP image mode"):
         im.save(f)
 
 
diff --git a/Tests/test_file_png.py b/Tests/test_file_png.py
index 0f0886ab8..15f67385a 100644
--- a/Tests/test_file_png.py
+++ b/Tests/test_file_png.py
@@ -100,11 +100,11 @@ class TestFilePng:
             assert im.format == "PNG"
             assert im.get_format_mimetype() == "image/png"
 
-        for mode in ["1", "L", "P", "RGB", "I", "I;16", "I;16B"]:
+        for mode in ["1", "L", "P", "RGB", "I;16", "I;16B"]:
             im = hopper(mode)
             im.save(test_file)
             with Image.open(test_file) as reloaded:
-                if mode in ("I", "I;16B"):
+                if mode == "I;16B":
                     reloaded = reloaded.convert(mode)
                 assert_image_equal(reloaded, im)
 
@@ -801,6 +801,16 @@ class TestFilePng:
         with Image.open("Tests/images/truncated_end_chunk.png") as im:
             assert_image_equal_tofile(im, "Tests/images/hopper.png")
 
+    def test_deprecation(self, tmp_path: Path) -> None:
+        test_file = tmp_path / "out.png"
+
+        im = hopper("I")
+        with pytest.warns(DeprecationWarning):
+            im.save(test_file)
+
+        with Image.open(test_file) as reloaded:
+            assert_image_equal(im, reloaded.convert("I"))
+
 
 @pytest.mark.skipif(is_win32(), reason="Requires Unix or macOS")
 @skip_unless_feature("zlib")
diff --git a/Tests/test_file_ppm.py b/Tests/test_file_ppm.py
index c7d1f4df4..68f2f9468 100644
--- a/Tests/test_file_ppm.py
+++ b/Tests/test_file_ppm.py
@@ -294,9 +294,10 @@ def test_header_token_too_long(tmp_path: Path, data: bytes) -> None:
     with open(path, "wb") as f:
         f.write(data)
 
-    with pytest.raises(ValueError, match="Token too long in file header: "):
+    with pytest.raises(ValueError) as e:
         with Image.open(path):
             pass
+    assert "Token too long in file header: " in repr(e)
 
 
 def test_truncated_file(tmp_path: Path) -> None:
diff --git a/Tests/test_file_qoi.py b/Tests/test_file_qoi.py
index 7ce1da209..b9becb24f 100644
--- a/Tests/test_file_qoi.py
+++ b/Tests/test_file_qoi.py
@@ -1,10 +1,12 @@
 from __future__ import annotations
 
+from pathlib import Path
+
 import pytest
 
 from PIL import Image, QoiImagePlugin
 
-from .helper import assert_image_equal_tofile
+from .helper import assert_image_equal_tofile, hopper
 
 
 def test_sanity() -> None:
@@ -34,3 +36,22 @@ def test_op_index() -> None:
     # QOI_OP_INDEX as the first chunk
     with Image.open("Tests/images/op_index.qoi") as im:
         assert im.getpixel((0, 0)) == (0, 0, 0, 0)
+
+
+def test_save(tmp_path: Path) -> None:
+    f = tmp_path / "temp.qoi"
+
+    im = hopper()
+    im.save(f, colorspace="sRGB")
+
+    assert_image_equal_tofile(im, f)
+
+    for path in ("Tests/images/default_font.png", "Tests/images/pil123rgba.png"):
+        with Image.open(path) as im:
+            im.save(f)
+
+            assert_image_equal_tofile(im, f)
+
+    im = hopper("P")
+    with pytest.raises(ValueError, match="Unsupported QOI image mode"):
+        im.save(f)
diff --git a/docs/deprecations.rst b/docs/deprecations.rst
index a5d89408b..def98b80a 100644
--- a/docs/deprecations.rst
+++ b/docs/deprecations.rst
@@ -201,6 +201,20 @@ Image.fromarray mode parameter
 The ``mode`` parameter in :py:meth:`~PIL.Image.fromarray()` has been deprecated. The
 mode can be automatically determined from the object's shape and type instead.
 
+Saving I mode images as PNG
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. deprecated:: 11.3.0
+
+In order to fit the 32 bits of I mode images into PNG, when PNG images can only contain
+at most 16 bits for a channel, Pillow has been clipping the values. Rather than quietly
+changing the data, this is now deprecated. Instead, the image can be converted to
+another mode before saving::
+
+    from PIL import Image
+    im = Image.new("I", (1, 1))
+    im.convert("I;16").save("out.png")
+
 Removed features
 ----------------
 
diff --git a/docs/handbook/image-file-formats.rst b/docs/handbook/image-file-formats.rst
index 5ca549c37..a15e84574 100644
--- a/docs/handbook/image-file-formats.rst
+++ b/docs/handbook/image-file-formats.rst
@@ -1082,6 +1082,26 @@ Pillow reads and writes PBM, PGM, PPM and PNM files containing ``1``, ``L``, ``I
 
 Since Pillow 9.2.0, "plain" (P1 to P3) formats can be read as well.
 
+QOI
+^^^
+
+.. versionadded:: 9.5.0
+
+Pillow reads and writes images in Quite OK Image format using a Python codec. If you
+wish to write code specifically for this format, :pypi:`qoi` is an alternative library
+that uses C to decode the image and interfaces with NumPy.
+
+.. _qoi-saving:
+
+Saving
+~~~~~~
+
+The :py:meth:`~PIL.Image.Image.save` method can take the following keyword arguments:
+
+**colorspace**
+    If set to "sRGB", the colorspace will be written as sRGB with linear alpha, instead
+    of all channels being linear.
+
 SGI
 ^^^
 
@@ -1578,15 +1598,6 @@ PSD
 
 Pillow identifies and reads PSD files written by Adobe Photoshop 2.5 and 3.0.
 
-QOI
-^^^
-
-.. versionadded:: 9.5.0
-
-Pillow reads images in Quite OK Image format using a Python decoder. If you wish to
-write code specifically for this format, :pypi:`qoi` is an alternative library that
-uses C to decode the image and interfaces with NumPy.
-
 SUN
 ^^^
 
diff --git a/docs/releasenotes/11.3.0.rst b/docs/releasenotes/11.3.0.rst
index f0fa8c858..82e4d44b6 100644
--- a/docs/releasenotes/11.3.0.rst
+++ b/docs/releasenotes/11.3.0.rst
@@ -29,6 +29,18 @@ Image.fromarray mode parameter
 The ``mode`` parameter in :py:meth:`~PIL.Image.fromarray()` has been deprecated. The
 mode can be automatically determined from the object's shape and type instead.
 
+Saving I mode images as PNG
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In order to fit the 32 bits of I mode images into PNG, when PNG images can only contain
+at most 16 bits for a channel, Pillow has been clipping the values. Rather than quietly
+changing the data, this is now deprecated. Instead, the image can be converted to
+another mode before saving::
+
+    from PIL import Image
+    im = Image.new("I", (1, 1))
+    im.convert("I;16").save("out.png")
+
 API changes
 ===========
 
@@ -48,6 +60,26 @@ TODO
 Other changes
 =============
 
+Added QOI saving
+^^^^^^^^^^^^^^^^
+
+Support has been added for saving QOI images. ``colorspace`` can be used to specify the
+colorspace as sRGB with linear alpha, e.g. ``im.save("out.qoi", colorspace="sRGB")``.
+By default, all channels will be linear.
+
+Support using more screenshot utilities with ImageGrab on Linux
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+:py:meth:`~PIL.ImageGrab.grab` is now able to use GNOME Screenshot, grim or Spectacle
+on Linux in order to take a snapshot of the screen.
+
+Do not build against libavif < 1
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Pillow only supports libavif 1.0.0 or later. In order to prevent errors when building
+from source, if a user happens to have an earlier libavif on their system, Pillow will
+now ignore it.
+
 Python 3.14 beta
 ^^^^^^^^^^^^^^^^
 
diff --git a/src/PIL/PngImagePlugin.py b/src/PIL/PngImagePlugin.py
index f3815a122..1b9a89aef 100644
--- a/src/PIL/PngImagePlugin.py
+++ b/src/PIL/PngImagePlugin.py
@@ -48,6 +48,7 @@ from ._binary import i32be as i32
 from ._binary import o8
 from ._binary import o16be as o16
 from ._binary import o32be as o32
+from ._deprecate import deprecate
 from ._util import DeferredError
 
 TYPE_CHECKING = False
@@ -1368,6 +1369,8 @@ def _save(
     except KeyError as e:
         msg = f"cannot write mode {mode} as PNG"
         raise OSError(msg) from e
+    if outmode == "I":
+        deprecate("Saving I mode images as PNG", 13, stacklevel=4)
 
     #
     # write minimal PNG file
diff --git a/src/PIL/QoiImagePlugin.py b/src/PIL/QoiImagePlugin.py
index 75070abd7..dba5d809f 100644
--- a/src/PIL/QoiImagePlugin.py
+++ b/src/PIL/QoiImagePlugin.py
@@ -8,9 +8,12 @@
 from __future__ import annotations
 
 import os
+from typing import IO
 
 from . import Image, ImageFile
 from ._binary import i32be as i32
+from ._binary import o8
+from ._binary import o32be as o32
 
 
 def _accept(prefix: bytes) -> bool:
@@ -110,6 +113,122 @@ class QoiDecoder(ImageFile.PyDecoder):
         return -1, 0
 
 
+def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
+    if im.mode == "RGB":
+        channels = 3
+    elif im.mode == "RGBA":
+        channels = 4
+    else:
+        msg = "Unsupported QOI image mode"
+        raise ValueError(msg)
+
+    colorspace = 0 if im.encoderinfo.get("colorspace") == "sRGB" else 1
+
+    fp.write(b"qoif")
+    fp.write(o32(im.size[0]))
+    fp.write(o32(im.size[1]))
+    fp.write(o8(channels))
+    fp.write(o8(colorspace))
+
+    ImageFile._save(im, fp, [ImageFile._Tile("qoi", (0, 0) + im.size)])
+
+
+class QoiEncoder(ImageFile.PyEncoder):
+    _pushes_fd = True
+    _previous_pixel: tuple[int, int, int, int] | None = None
+    _previously_seen_pixels: dict[int, tuple[int, int, int, int]] = {}
+    _run = 0
+
+    def _write_run(self) -> bytes:
+        data = o8(0b11000000 | (self._run - 1))  # QOI_OP_RUN
+        self._run = 0
+        return data
+
+    def _delta(self, left: int, right: int) -> int:
+        result = (left - right) & 255
+        if result >= 128:
+            result -= 256
+        return result
+
+    def encode(self, bufsize: int) -> tuple[int, int, bytes]:
+        assert self.im is not None
+
+        self._previously_seen_pixels = {0: (0, 0, 0, 0)}
+        self._previous_pixel = (0, 0, 0, 255)
+
+        data = bytearray()
+        w, h = self.im.size
+        bands = Image.getmodebands(self.mode)
+
+        for y in range(h):
+            for x in range(w):
+                pixel = self.im.getpixel((x, y))
+                if bands == 3:
+                    pixel = (*pixel, 255)
+
+                if pixel == self._previous_pixel:
+                    self._run += 1
+                    if self._run == 62:
+                        data += self._write_run()
+                else:
+                    if self._run:
+                        data += self._write_run()
+
+                    r, g, b, a = pixel
+                    hash_value = (r * 3 + g * 5 + b * 7 + a * 11) % 64
+                    if self._previously_seen_pixels.get(hash_value) == pixel:
+                        data += o8(hash_value)  # QOI_OP_INDEX
+                    elif self._previous_pixel:
+                        self._previously_seen_pixels[hash_value] = pixel
+
+                        prev_r, prev_g, prev_b, prev_a = self._previous_pixel
+                        if prev_a == a:
+                            delta_r = self._delta(r, prev_r)
+                            delta_g = self._delta(g, prev_g)
+                            delta_b = self._delta(b, prev_b)
+
+                            if (
+                                -2 <= delta_r < 2
+                                and -2 <= delta_g < 2
+                                and -2 <= delta_b < 2
+                            ):
+                                data += o8(
+                                    0b01000000
+                                    | (delta_r + 2) << 4
+                                    | (delta_g + 2) << 2
+                                    | (delta_b + 2)
+                                )  # QOI_OP_DIFF
+                            else:
+                                delta_gr = self._delta(delta_r, delta_g)
+                                delta_gb = self._delta(delta_b, delta_g)
+                                if (
+                                    -8 <= delta_gr < 8
+                                    and -32 <= delta_g < 32
+                                    and -8 <= delta_gb < 8
+                                ):
+                                    data += o8(
+                                        0b10000000 | (delta_g + 32)
+                                    )  # QOI_OP_LUMA
+                                    data += o8((delta_gr + 8) << 4 | (delta_gb + 8))
+                                else:
+                                    data += o8(0b11111110)  # QOI_OP_RGB
+                                    data += bytes(pixel[:3])
+                        else:
+                            data += o8(0b11111111)  # QOI_OP_RGBA
+                            data += bytes(pixel)
+
+                self._previous_pixel = pixel
+
+        if self._run:
+            data += self._write_run()
+        data += bytes((0, 0, 0, 0, 0, 0, 0, 1))  # padding
+
+        return len(data), 0, data
+
+
 Image.register_open(QoiImageFile.format, QoiImageFile, _accept)
 Image.register_decoder("qoi", QoiDecoder)
 Image.register_extension(QoiImageFile.format, ".qoi")
+
+Image.register_save(QoiImageFile.format, _save)
+Image.register_encoder("qoi", QoiEncoder)
diff --git a/src/PIL/_deprecate.py b/src/PIL/_deprecate.py
index 9f9d8bbc9..170d44490 100644
--- a/src/PIL/_deprecate.py
+++ b/src/PIL/_deprecate.py
@@ -12,6 +12,7 @@ def deprecate(
     *,
     action: str | None = None,
     plural: bool = False,
+    stacklevel: int = 3,
 ) -> None:
     """
     Deprecations helper.
@@ -67,5 +68,5 @@ def deprecate(
     warnings.warn(
         f"{deprecated} {is_} deprecated and will be removed in {removed}{action}",
         DeprecationWarning,
-        stacklevel=3,
+        stacklevel=stacklevel,
     )
diff --git a/src/_imaging.c b/src/_imaging.c
index 2a7bc8d3f..6241dc3ca 100644
--- a/src/_imaging.c
+++ b/src/_imaging.c
@@ -338,12 +338,6 @@ static const char *no_palette = "image has no palette";
 static const char *readonly = "image is readonly";
 /* static const char* no_content = "image has no content"; */
 
-void *
-ImagingError_OSError(void) {
-    PyErr_SetString(PyExc_OSError, "error when accessing file");
-    return NULL;
-}
-
 void *
 ImagingError_MemoryError(void) {
     return PyErr_NoMemory();
@@ -369,11 +363,6 @@ ImagingError_ValueError(const char *message) {
     return NULL;
 }
 
-void
-ImagingError_Clear(void) {
-    PyErr_Clear();
-}
-
 /* -------------------------------------------------------------------- */
 /* HELPERS                                */
 /* -------------------------------------------------------------------- */
diff --git a/src/libImaging/File.c b/src/libImaging/File.c
index 76d0abccc..901fe83ad 100644
--- a/src/libImaging/File.c
+++ b/src/libImaging/File.c
@@ -54,7 +54,7 @@ ImagingSavePPM(Imaging im, const char *outfile) {
 
     fp = fopen(outfile, "wb");
     if (!fp) {
-        (void)ImagingError_OSError();
+        PyErr_SetString(PyExc_OSError, "error when accessing file");
         return 0;
     }
 
diff --git a/src/libImaging/Imaging.h b/src/libImaging/Imaging.h
index 39ecdbff6..bfe67d462 100644
--- a/src/libImaging/Imaging.h
+++ b/src/libImaging/Imaging.h
@@ -270,8 +270,6 @@ ImagingSectionLeave(ImagingSectionCookie *cookie);
 /* Exceptions */
 /* ---------- */
 
-extern void *
-ImagingError_OSError(void);
 extern void *
 ImagingError_MemoryError(void);
 extern void *
@@ -280,8 +278,6 @@ extern void *
 ImagingError_Mismatch(void); /* maps to ValueError by default */
 extern void *
 ImagingError_ValueError(const char *message);
-extern void
-ImagingError_Clear(void);
 
 /* Transform callbacks */
 /* ------------------- */
diff --git a/src/libImaging/Storage.c b/src/libImaging/Storage.c
index 11d6c06cc..6fe26e1bd 100644
--- a/src/libImaging/Storage.c
+++ b/src/libImaging/Storage.c
@@ -645,7 +645,7 @@ ImagingNewInternal(const char *mode, int xsize, int ysize, int dirty) {
         return im;
     }
 
-    ImagingError_Clear();
+    PyErr_Clear();
 
     // Try to allocate the image once more with smallest possible block size
     MUTEX_LOCK(&ImagingDefaultArena.mutex);
diff --git a/winbuild/build_prepare.py b/winbuild/build_prepare.py
index 0cc383733..098716b60 100644
--- a/winbuild/build_prepare.py
+++ b/winbuild/build_prepare.py
@@ -118,7 +118,7 @@ V = {
     "LCMS2": "2.17",
     "LIBAVIF": "1.3.0",
     "LIBIMAGEQUANT": "4.3.4",
-    "LIBPNG": "1.6.48",
+    "LIBPNG": "1.6.49",
     "LIBWEBP": "1.5.0",
     "OPENJPEG": "2.5.3",
     "TIFF": "4.7.0",