diff --git a/CHANGES.rst b/CHANGES.rst
index c3e60acff..060569ab5 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,6 +5,60 @@ Changelog (Pillow)
 9.3.0 (unreleased)
 ------------------
 
+- Added support for reading BMP images with RLE4 compression #6674
+  [npjg, radarhere]
+
+- Decode JPEG compressed BLP1 data in original mode #6678
+  [radarhere]
+
+- Added GPS TIFF tag info #6661
+  [radarhere]
+
+- Added conversion between RGB/RGBA/RGBX and LAB #6647
+  [radarhere]
+
+- Do not attempt normalization if mode is already normal #6644
+  [radarhere]
+
+- Fixed seeking to an L frame in a GIF #6576
+  [radarhere]
+
+- Consider all frames when selecting mode for PNG save_all #6610
+  [radarhere]
+
+- Don't reassign crc on ChunkStream close #6627
+  [wiredfool, radarhere]
+
+- Raise a warning if NumPy failed to raise an error during conversion #6594
+  [radarhere]
+
+- Show all frames in ImageShow #6611
+  [radarhere]
+
+- Allow FLI palette chunk to not be first #6626
+  [radarhere]
+
+- If first GIF frame has transparency for RGB_ALWAYS loading strategy, use RGBA mode #6592
+  [radarhere]
+
+- Round box position to integer when pasting embedded color #6517
+  [radarhere, nulano]
+
+- Removed EXIF prefix when saving WebP #6582
+  [radarhere]
+
+- Pad IM palette to 768 bytes when saving #6579
+  [radarhere]
+
+- Added DDS BC6H reading #6449
+  [ShadelessFox, REDxEYE, radarhere]
+
+- Added support for opening WhiteIsZero 16-bit integer TIFF images #6642
+  [JayWiz, radarhere]
+
+- Raise an error when allocating translucent color to RGB palette #6654
+  [jsbueno, radarhere]
+
 - Added reading of TIFF child images #6569
   [radarhere]
 
diff --git a/Tests/helper.py b/Tests/helper.py
index 13c6955e4..0d1d03ac8 100644
--- a/Tests/helper.py
+++ b/Tests/helper.py
@@ -208,12 +208,11 @@ class PillowLeakTestCase:
             #     ru_maxrss
             # This is the maximum resident set size utilized (in bytes).
             return mem / 1024  # Kb
-        else:
-            # linux
-            # man 2 getrusage
-            #        ru_maxrss (since Linux 2.6.32)
-            #  This is the maximum resident set size used (in kilobytes).
-            return mem  # Kb
+        # linux
+        # man 2 getrusage
+        #        ru_maxrss (since Linux 2.6.32)
+        #  This is the maximum resident set size used (in kilobytes).
+        return mem  # Kb
 
     def _test_leak(self, core):
         start_mem = self._get_mem_usage()
@@ -285,7 +284,7 @@ def magick_command():
 
     if imagemagick and shutil.which(imagemagick[0]):
         return imagemagick
-    elif graphicsmagick and shutil.which(graphicsmagick[0]):
+    if graphicsmagick and shutil.which(graphicsmagick[0]):
         return graphicsmagick
 
 
diff --git a/Tests/images/bc6h.dds b/Tests/images/bc6h.dds
new file mode 100644
index 000000000..77993a0c1
Binary files /dev/null and b/Tests/images/bc6h.dds differ
diff --git a/Tests/images/bc6h.png b/Tests/images/bc6h.png
new file mode 100644
index 000000000..609f11489
Binary files /dev/null and b/Tests/images/bc6h.png differ
diff --git a/Tests/images/bc6h_sf.dds b/Tests/images/bc6h_sf.dds
new file mode 100644
index 000000000..2ab1b195b
Binary files /dev/null and b/Tests/images/bc6h_sf.dds differ
diff --git a/Tests/images/bc6h_sf.png b/Tests/images/bc6h_sf.png
new file mode 100644
index 000000000..6a3b73d5f
Binary files /dev/null and b/Tests/images/bc6h_sf.png differ
diff --git a/Tests/images/blp/blp1_jpeg2.blp b/Tests/images/blp/blp1_jpeg2.blp
new file mode 100644
index 000000000..890180e9b
Binary files /dev/null and b/Tests/images/blp/blp1_jpeg2.blp differ
diff --git a/Tests/images/bw_gradient.imt b/Tests/images/bw_gradient.imt
new file mode 100644
index 000000000..d765cf95f
Binary files /dev/null and b/Tests/images/bw_gradient.imt differ
diff --git a/Tests/images/hopper_palette_chunk_second.fli b/Tests/images/hopper_palette_chunk_second.fli
new file mode 100644
index 000000000..54447de0a
Binary files /dev/null and b/Tests/images/hopper_palette_chunk_second.fli differ
diff --git a/Tests/images/no_palette_after_rgb.gif b/Tests/images/no_palette_after_rgb.gif
new file mode 100644
index 000000000..8704c464c
Binary files /dev/null and b/Tests/images/no_palette_after_rgb.gif differ
diff --git a/Tests/images/palette_not_needed_for_second_frame.gif b/Tests/images/palette_not_needed_for_second_frame.gif
new file mode 100644
index 000000000..0617291d1
Binary files /dev/null and b/Tests/images/palette_not_needed_for_second_frame.gif differ
diff --git a/Tests/images/text_float_coord.png b/Tests/images/text_float_coord.png
new file mode 100644
index 000000000..49468698c
Binary files /dev/null and b/Tests/images/text_float_coord.png differ
diff --git a/Tests/images/text_float_coord_1_alt.png b/Tests/images/text_float_coord_1_alt.png
new file mode 100644
index 000000000..50bdac3d8
Binary files /dev/null and b/Tests/images/text_float_coord_1_alt.png differ
diff --git a/Tests/images/unimplemented_dxgi_format.dds b/Tests/images/unimplemented_dxgi_format.dds
index 5ecb42006..70860f2fc 100644
Binary files a/Tests/images/unimplemented_dxgi_format.dds and b/Tests/images/unimplemented_dxgi_format.dds differ
diff --git a/Tests/test_file_apng.py b/Tests/test_file_apng.py
index cdaad5940..1f5567163 100644
--- a/Tests/test_file_apng.py
+++ b/Tests/test_file_apng.py
@@ -647,6 +647,16 @@ def test_seek_after_close():
         im.seek(0)
 
 
+@pytest.mark.parametrize("mode", ("RGBA", "RGB", "P"))
+def test_different_modes_in_later_frames(mode, tmp_path):
+    test_file = str(tmp_path / "temp.png")
+
+    im = Image.new("L", (1, 1))
+    im.save(test_file, save_all=True, append_images=[Image.new(mode, (1, 1))])
+    with Image.open(test_file) as reloaded:
+        assert reloaded.mode == mode
+
+
 def test_constants_deprecation():
     for enum, prefix in {
         PngImagePlugin.Disposal: "APNG_DISPOSE_",
diff --git a/Tests/test_file_blp.py b/Tests/test_file_blp.py
index c1fae44ca..ba2781820 100644
--- a/Tests/test_file_blp.py
+++ b/Tests/test_file_blp.py
@@ -14,6 +14,9 @@ def test_load_blp1():
     with Image.open("Tests/images/blp/blp1_jpeg.blp") as im:
         assert_image_equal_tofile(im, "Tests/images/blp/blp1_jpeg.png")
 
+    with Image.open("Tests/images/blp/blp1_jpeg2.blp") as im:
+        im.load()
+
 
 def test_load_blp2_raw():
     with Image.open("Tests/images/blp/blp2_raw.blp") as im:
diff --git a/Tests/test_file_bmp.py b/Tests/test_file_bmp.py
index f6860a9a4..5f6d52355 100644
--- a/Tests/test_file_bmp.py
+++ b/Tests/test_file_bmp.py
@@ -176,6 +176,11 @@ def test_rle8():
                 im.load()
 
 
+def test_rle4():
+    with Image.open("Tests/images/bmp/g/pal4rle.bmp") as im:
+        assert_image_similar_tofile(im, "Tests/images/bmp/g/pal4.bmp", 12)
+
+
 @pytest.mark.parametrize(
     "file_name,length",
     (
diff --git a/Tests/test_file_dds.py b/Tests/test_file_dds.py
index 351001199..4b9f8949e 100644
--- a/Tests/test_file_dds.py
+++ b/Tests/test_file_dds.py
@@ -16,6 +16,8 @@ TEST_FILE_DX10_BC5_TYPELESS = "Tests/images/bc5_typeless.dds"
 TEST_FILE_DX10_BC5_UNORM = "Tests/images/bc5_unorm.dds"
 TEST_FILE_DX10_BC5_SNORM = "Tests/images/bc5_snorm.dds"
 TEST_FILE_BC5S = "Tests/images/bc5s.dds"
+TEST_FILE_BC6H = "Tests/images/bc6h.dds"
+TEST_FILE_BC6HS = "Tests/images/bc6h_sf.dds"
 TEST_FILE_DX10_BC7 = "Tests/images/bc7-argb-8bpp_MipMaps-1.dds"
 TEST_FILE_DX10_BC7_UNORM_SRGB = "Tests/images/DXGI_FORMAT_BC7_UNORM_SRGB.dds"
 TEST_FILE_DX10_R8G8B8A8 = "Tests/images/argb-32bpp_MipMaps-1.dds"
@@ -114,6 +116,20 @@ def test_dx10_bc5(image_path, expected_path):
         assert_image_equal_tofile(im, expected_path.replace(".dds", ".png"))
 
 
+@pytest.mark.parametrize("image_path", (TEST_FILE_BC6H, TEST_FILE_BC6HS))
+def test_dx10_bc6h(image_path):
+    """Check DX10 BC6H/BC6HS images can be opened"""
+
+    with Image.open(image_path) as im:
+        im.load()
+
+        assert im.format == "DDS"
+        assert im.mode == "RGB"
+        assert im.size == (128, 128)
+
+        assert_image_equal_tofile(im, image_path.replace(".dds", ".png"))
+
+
 def test_dx10_bc7():
     """Check DX10 images can be opened"""
 
diff --git a/Tests/test_file_fli.py b/Tests/test_file_fli.py
index a7d43d2e9..b8b999d70 100644
--- a/Tests/test_file_fli.py
+++ b/Tests/test_file_fli.py
@@ -4,7 +4,7 @@ import pytest
 
 from PIL import FliImagePlugin, Image
 
-from .helper import assert_image_equal_tofile, is_pypy
+from .helper import assert_image_equal, assert_image_equal_tofile, is_pypy
 
 # created as an export of a palette image from Gimp2.6
 # save as...-> hopper.fli, default options.
@@ -79,6 +79,12 @@ def test_invalid_file():
         FliImagePlugin.FliImageFile(invalid_file)
 
 
+def test_palette_chunk_second():
+    with Image.open("Tests/images/hopper_palette_chunk_second.fli") as im:
+        with Image.open(static_test_file) as expected:
+            assert_image_equal(im.convert("RGB"), expected.convert("RGB"))
+
+
 def test_n_frames():
     with Image.open(static_test_file) as im:
         assert im.n_frames == 1
diff --git a/Tests/test_file_gif.py b/Tests/test_file_gif.py
index 637be2be4..926f5c1ee 100644
--- a/Tests/test_file_gif.py
+++ b/Tests/test_file_gif.py
@@ -83,18 +83,40 @@ def test_l_mode_transparency():
         assert im.load()[0, 0] == 128
 
 
+def test_l_mode_after_rgb():
+    with Image.open("Tests/images/no_palette_after_rgb.gif") as im:
+        im.seek(1)
+        assert im.mode == "RGB"
+
+        im.seek(2)
+        assert im.mode == "RGB"
+
+
+def test_palette_not_needed_for_second_frame():
+    with Image.open("Tests/images/palette_not_needed_for_second_frame.gif") as im:
+        im.seek(1)
+        assert_image_similar(im, hopper("L").convert("RGB"), 8)
+
+
 def test_strategy():
+    with Image.open("Tests/images/iss634.gif") as im:
+        expected_rgb_always = im.convert("RGB")
+
     with Image.open("Tests/images/chi.gif") as im:
-        expected_zero = im.convert("RGB")
+        expected_rgb_always_rgba = im.convert("RGBA")
 
         im.seek(1)
-        expected_one = im.convert("RGB")
+        expected_different = im.convert("RGB")
 
     try:
         GifImagePlugin.LOADING_STRATEGY = GifImagePlugin.LoadingStrategy.RGB_ALWAYS
-        with Image.open("Tests/images/chi.gif") as im:
+        with Image.open("Tests/images/iss634.gif") as im:
             assert im.mode == "RGB"
-            assert_image_equal(im, expected_zero)
+            assert_image_equal(im, expected_rgb_always)
+
+        with Image.open("Tests/images/chi.gif") as im:
+            assert im.mode == "RGBA"
+            assert_image_equal(im, expected_rgb_always_rgba)
 
         GifImagePlugin.LOADING_STRATEGY = (
             GifImagePlugin.LoadingStrategy.RGB_AFTER_DIFFERENT_PALETTE_ONLY
@@ -105,7 +127,7 @@ def test_strategy():
 
             im.seek(1)
             assert im.mode == "P"
-            assert_image_equal(im.convert("RGB"), expected_one)
+            assert_image_equal(im.convert("RGB"), expected_different)
 
         # Change to RGB mode when a frame has an individual palette
         with Image.open("Tests/images/iss634.gif") as im:
diff --git a/Tests/test_file_im.py b/Tests/test_file_im.py
index e458a197c..5cf93713b 100644
--- a/Tests/test_file_im.py
+++ b/Tests/test_file_im.py
@@ -86,6 +86,18 @@ def test_roundtrip(mode, tmp_path):
     assert_image_equal_tofile(im, out)
 
 
+def test_small_palette(tmp_path):
+    im = Image.new("P", (1, 1))
+    colors = [0, 1, 2]
+    im.putpalette(colors)
+
+    out = str(tmp_path / "temp.im")
+    im.save(out)
+
+    with Image.open(out) as reloaded:
+        assert reloaded.getpalette() == colors + [0] * 765
+
+
 def test_save_unsupported_mode(tmp_path):
     out = str(tmp_path / "temp.im")
     im = hopper("HSV")
diff --git a/Tests/test_file_imt.py b/Tests/test_file_imt.py
new file mode 100644
index 000000000..f56acc429
--- /dev/null
+++ b/Tests/test_file_imt.py
@@ -0,0 +1,19 @@
+import io
+
+import pytest
+
+from PIL import Image, ImtImagePlugin
+
+from .helper import assert_image_equal_tofile
+
+
+def test_sanity():
+    with Image.open("Tests/images/bw_gradient.imt") as im:
+        assert_image_equal_tofile(im, "Tests/images/bw_gradient.png")
+
+
+@pytest.mark.parametrize("data", (b"\n", b"\n-", b"width 1\n"))
+def test_invalid_file(data):
+    with io.BytesIO(data) as fp:
+        with pytest.raises(SyntaxError):
+            ImtImagePlugin.ImtImageFile(fp)
diff --git a/Tests/test_file_jpeg.py b/Tests/test_file_jpeg.py
index adbb72aa5..fa96e425b 100644
--- a/Tests/test_file_jpeg.py
+++ b/Tests/test_file_jpeg.py
@@ -30,7 +30,7 @@ from .helper import (
 )
 
 try:
-    import defusedxml.ElementTree as ElementTree
+    from defusedxml import ElementTree
 except ImportError:
     ElementTree = None
 
diff --git a/Tests/test_file_libtiff.py b/Tests/test_file_libtiff.py
index d9066c589..58d3aac06 100644
--- a/Tests/test_file_libtiff.py
+++ b/Tests/test_file_libtiff.py
@@ -934,7 +934,7 @@ class TestFileLibTiff(LibTiffTestCase):
         im.save(out, exif=tags, compression=compression)
 
         with Image.open(out) as reloaded:
-            for tag in tags.keys():
+            for tag in tags:
                 assert tag not in reloaded.getexif()
 
     def test_old_style_jpeg(self):
diff --git a/Tests/test_file_png.py b/Tests/test_file_png.py
index 1af0223eb..37235fe6f 100644
--- a/Tests/test_file_png.py
+++ b/Tests/test_file_png.py
@@ -20,7 +20,7 @@ from .helper import (
 )
 
 try:
-    import defusedxml.ElementTree as ElementTree
+    from defusedxml import ElementTree
 except ImportError:
     ElementTree = None
 
diff --git a/Tests/test_file_ppm.py b/Tests/test_file_ppm.py
index 5c6376caf..fbcbea6c6 100644
--- a/Tests/test_file_ppm.py
+++ b/Tests/test_file_ppm.py
@@ -240,8 +240,8 @@ def test_header_token_too_long(tmp_path):
 def test_truncated_file(tmp_path):
     # Test EOF in header
     path = str(tmp_path / "temp.pgm")
-    with open(path, "w") as f:
-        f.write("P6")
+    with open(path, "wb") as f:
+        f.write(b"P6")
 
     with pytest.raises(ValueError) as e:
         with Image.open(path):
@@ -256,11 +256,11 @@ def test_truncated_file(tmp_path):
             im.load()
 
 
-@pytest.mark.parametrize("maxval", (0, 65536))
+@pytest.mark.parametrize("maxval", (b"0", b"65536"))
 def test_invalid_maxval(maxval, tmp_path):
     path = str(tmp_path / "temp.ppm")
-    with open(path, "w") as f:
-        f.write("P6\n3 1 " + str(maxval))
+    with open(path, "wb") as f:
+        f.write(b"P6\n3 1 " + maxval)
 
     with pytest.raises(ValueError) as e:
         with Image.open(path):
@@ -283,13 +283,13 @@ def test_neg_ppm():
 def test_mimetypes(tmp_path):
     path = str(tmp_path / "temp.pgm")
 
-    with open(path, "w") as f:
-        f.write("P4\n128 128\n255")
+    with open(path, "wb") as f:
+        f.write(b"P4\n128 128\n255")
     with Image.open(path) as im:
         assert im.get_format_mimetype() == "image/x-portable-bitmap"
 
-    with open(path, "w") as f:
-        f.write("PyCMYK\n128 128\n255")
+    with open(path, "wb") as f:
+        f.write(b"PyCMYK\n128 128\n255")
     with Image.open(path) as im:
         assert im.get_format_mimetype() == "image/x-portable-anymap"
 
diff --git a/Tests/test_file_tiff.py b/Tests/test_file_tiff.py
index 1a5ba594f..a32e6a005 100644
--- a/Tests/test_file_tiff.py
+++ b/Tests/test_file_tiff.py
@@ -18,7 +18,7 @@ from .helper import (
 )
 
 try:
-    import defusedxml.ElementTree as ElementTree
+    from defusedxml import ElementTree
 except ImportError:
     ElementTree = None
 
diff --git a/Tests/test_file_webp_metadata.py b/Tests/test_file_webp_metadata.py
index e6d6fc63f..f77a245c0 100644
--- a/Tests/test_file_webp_metadata.py
+++ b/Tests/test_file_webp_metadata.py
@@ -55,9 +55,7 @@ def test_write_exif_metadata():
     test_buffer.seek(0)
     with Image.open(test_buffer) as webp_image:
         webp_exif = webp_image.info.get("exif", None)
-    assert webp_exif
-    if webp_exif:
-        assert webp_exif == expected_exif, "WebP EXIF didn't match"
+    assert webp_exif == expected_exif[6:], "WebP EXIF didn't match"
 
 
 def test_read_icc_profile():
diff --git a/Tests/test_image.py b/Tests/test_image.py
index ab945e946..e57903490 100644
--- a/Tests/test_image.py
+++ b/Tests/test_image.py
@@ -129,8 +129,6 @@ class TestImage:
             im.size = (3, 4)
 
     def test_invalid_image(self):
-        import io
-
         im = io.BytesIO(b"")
         with pytest.raises(UnidentifiedImageError):
             with Image.open(im):
@@ -699,15 +697,15 @@ class TestImage:
     def test_empty_exif(self):
         with Image.open("Tests/images/exif.png") as im:
             exif = im.getexif()
-        assert dict(exif) != {}
+        assert dict(exif)
 
         # Test that exif data is cleared after another load
         exif.load(None)
-        assert dict(exif) == {}
+        assert not dict(exif)
 
         # Test loading just the EXIF header
         exif.load(b"Exif\x00\x00")
-        assert dict(exif) == {}
+        assert not dict(exif)
 
     @mark_if_feature_version(
         pytest.mark.valgrind_known_error, "libjpeg_turbo", "2.0", reason="Known Failing"
diff --git a/Tests/test_image_access.py b/Tests/test_image_access.py
index bb09a7708..955740b95 100644
--- a/Tests/test_image_access.py
+++ b/Tests/test_image_access.py
@@ -131,8 +131,7 @@ class TestImageGetPixel(AccessTest):
         bands = Image.getmodebands(mode)
         if bands == 1:
             return 1
-        else:
-            return tuple(range(1, bands + 1))
+        return tuple(range(1, bands + 1))
 
     def check(self, mode, c=None):
         if not c:
@@ -345,13 +344,14 @@ class TestCffi(AccessTest):
 
     @pytest.mark.parametrize("mode", ("P", "PA"))
     def test_p_putpixel_rgb_rgba(self, mode):
-        for color in [(255, 0, 0), (255, 0, 0, 127)]:
+        for color in ((255, 0, 0), (255, 0, 0, 127 if mode == "PA" else 255)):
             im = Image.new(mode, (1, 1))
             access = PyAccess.new(im, False)
             access.putpixel((0, 0), color)
 
-            alpha = color[3] if len(color) == 4 and mode == "PA" else 255
-            assert im.convert("RGBA").getpixel((0, 0)) == (255, 0, 0, alpha)
+            if len(color) == 3:
+                color += (255,)
+            assert im.convert("RGBA").getpixel((0, 0)) == color
 
 
 class TestImagePutPixelError(AccessTest):
@@ -414,7 +414,7 @@ class TestEmbeddable:
     def test_embeddable(self):
         import ctypes
 
-        with open("embed_pil.c", "w") as fh:
+        with open("embed_pil.c", "w", encoding="utf-8") as fh:
             fh.write(
                 """
 #include "Python.h"
diff --git a/Tests/test_image_array.py b/Tests/test_image_array.py
index 7e5fd6fe1..ae3518e44 100644
--- a/Tests/test_image_array.py
+++ b/Tests/test_image_array.py
@@ -35,10 +35,13 @@ def test_toarray():
     test_with_dtype(numpy.float64)
     test_with_dtype(numpy.uint8)
 
-    if parse_version(numpy.__version__) >= parse_version("1.23"):
-        with Image.open("Tests/images/truncated_jpeg.jpg") as im_truncated:
+    with Image.open("Tests/images/truncated_jpeg.jpg") as im_truncated:
+        if parse_version(numpy.__version__) >= parse_version("1.23"):
             with pytest.raises(OSError):
                 numpy.array(im_truncated)
+        else:
+            with pytest.warns(UserWarning):
+                numpy.array(im_truncated)
 
 
 def test_fromarray():
diff --git a/Tests/test_image_convert.py b/Tests/test_image_convert.py
index 1a78f8b4c..902d8bf8f 100644
--- a/Tests/test_image_convert.py
+++ b/Tests/test_image_convert.py
@@ -38,6 +38,12 @@ def test_sanity():
             convert(im, output_mode)
 
 
+def test_unsupported_conversion():
+    im = hopper()
+    with pytest.raises(ValueError):
+        im.convert("INVALID")
+
+
 def test_default():
 
     im = hopper("P")
@@ -242,6 +248,17 @@ def test_p2pa_palette():
     assert im_pa.getpalette() == im.getpalette()
 
 
+@pytest.mark.parametrize("mode", ("RGB", "RGBA", "RGBX"))
+def test_rgb_lab(mode):
+    im = Image.new(mode, (1, 1))
+    converted_im = im.convert("LAB")
+    assert converted_im.getpixel((0, 0)) == (0, 128, 128)
+
+    im = Image.new("LAB", (1, 1), (255, 0, 0))
+    converted_im = im.convert(mode)
+    assert converted_im.getpixel((0, 0))[:3] == (0, 255, 255)
+
+
 def test_matrix_illegal_conversion():
     # Arrange
     im = hopper("CMYK")
diff --git a/Tests/test_imagefont.py b/Tests/test_imagefont.py
index a374e24c5..e5cf8b631 100644
--- a/Tests/test_imagefont.py
+++ b/Tests/test_imagefont.py
@@ -935,7 +935,30 @@ def test_standard_embedded_color(layout_engine):
     d = ImageDraw.Draw(im)
     d.text((10, 10), txt, font=ttf, fill="#fa6", embedded_color=True)
 
-    assert_image_similar_tofile(im, "Tests/images/standard_embedded.png", 6.2)
+    assert_image_similar_tofile(im, "Tests/images/standard_embedded.png", 3.1)
+
+
+@pytest.mark.parametrize("fontmode", ("1", "L", "RGBA"))
+def test_float_coord(layout_engine, fontmode):
+    txt = "Hello World!"
+    ttf = ImageFont.truetype(FONT_PATH, 40, layout_engine=layout_engine)
+
+    im = Image.new("RGB", (300, 64), "white")
+    d = ImageDraw.Draw(im)
+    if fontmode == "1":
+        d.fontmode = "1"
+
+    embedded_color = fontmode == "RGBA"
+    d.text((9.5, 9.5), txt, font=ttf, fill="#fa6", embedded_color=embedded_color)
+    try:
+        assert_image_similar_tofile(im, "Tests/images/text_float_coord.png", 3.9)
+    except AssertionError:
+        if fontmode == "1" and layout_engine == ImageFont.Layout.BASIC:
+            assert_image_similar_tofile(
+                im, "Tests/images/text_float_coord_1_alt.png", 1
+            )
+        else:
+            raise
 
 
 def test_cbdt(layout_engine):
diff --git a/Tests/test_imagemath.py b/Tests/test_imagemath.py
index 39d91eade..fe7ac9a7a 100644
--- a/Tests/test_imagemath.py
+++ b/Tests/test_imagemath.py
@@ -6,10 +6,8 @@ from PIL import Image, ImageMath
 def pixel(im):
     if hasattr(im, "im"):
         return f"{im.mode} {repr(im.getpixel((0, 0)))}"
-    else:
-        if isinstance(im, int):
-            return int(im)  # hack to deal with booleans
-        print(im)
+    if isinstance(im, int):
+        return int(im)  # hack to deal with booleans
 
 
 A = Image.new("L", (1, 1), 1)
diff --git a/Tests/test_imagepalette.py b/Tests/test_imagepalette.py
index 475d249ed..5bda28117 100644
--- a/Tests/test_imagepalette.py
+++ b/Tests/test_imagepalette.py
@@ -50,6 +50,16 @@ def test_getcolor():
         palette.getcolor("unknown")
 
 
+def test_getcolor_rgba_color_rgb_palette():
+    palette = ImagePalette.ImagePalette("RGB")
+
+    # Opaque RGBA colors are converted
+    assert palette.getcolor((0, 0, 0, 255)) == palette.getcolor((0, 0, 0))
+
+    with pytest.raises(ValueError):
+        palette.getcolor((0, 0, 0, 128))
+
+
 @pytest.mark.parametrize(
     "index, palette",
     [
diff --git a/docs/handbook/concepts.rst b/docs/handbook/concepts.rst
index 66eeaf6f8..a9b33e437 100644
--- a/docs/handbook/concepts.rst
+++ b/docs/handbook/concepts.rst
@@ -60,7 +60,10 @@ Pillow also provides limited support for a few additional modes, including:
     * ``BGR;24`` (24-bit reversed true colour)
     * ``BGR;32`` (32-bit reversed true colour)
 
-However, Pillow doesn’t support user-defined modes; if you need to handle band
+Apart from these additional modes, Pillow doesn't yet support multichannel
+images with a depth of more than 8 bits per channel.
+
+Pillow also doesn’t support user-defined modes; if you need to handle band
 combinations that are not listed above, use a sequence of Image objects.
 
 You can read the mode of an image through the :py:attr:`~PIL.Image.Image.mode`
diff --git a/docs/handbook/image-file-formats.rst b/docs/handbook/image-file-formats.rst
index dc629666c..1e79db68b 100644
--- a/docs/handbook/image-file-formats.rst
+++ b/docs/handbook/image-file-formats.rst
@@ -45,9 +45,9 @@ BMP
 ^^^
 
 Pillow reads and writes Windows and OS/2 BMP files containing ``1``, ``L``, ``P``,
-or ``RGB`` data. 16-colour images are read as ``P`` images. 4-bit run-length encoding
-is not supported. Support for reading 8-bit run-length encoding was added in Pillow
-9.1.0.
+or ``RGB`` data. 16-colour images are read as ``P`` images.
+Support for reading 8-bit run-length encoding was added in Pillow 9.1.0.
+Support for reading 4-bit run-length encoding was added in Pillow 9.3.0.
 
 Opening
 ~~~~~~~
@@ -56,7 +56,8 @@ The :py:meth:`~PIL.Image.open` method sets the following
 :py:attr:`~PIL.Image.Image.info` properties:
 
 **compression**
-    Set to ``bmp_rle`` if the file is run-length encoded.
+    Set to 1 if the file is a 256-color run-length encoded image.
+    Set to 2 if the file is a 16-color run-length encoded image.
 
 DDS
 ^^^
diff --git a/docs/releasenotes/9.1.0.rst b/docs/releasenotes/9.1.0.rst
index 57646e558..48ce6fef7 100644
--- a/docs/releasenotes/9.1.0.rst
+++ b/docs/releasenotes/9.1.0.rst
@@ -202,7 +202,7 @@ Pillow now builds binary wheels for musllinux, suitable for Linux distributions
 (rather than the glibc library used by manylinux wheels). See :pep:`656`.
 
 ImageShow temporary files on Unix
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 When calling :py:meth:`~PIL.Image.Image.show` or using :py:mod:`~PIL.ImageShow`,
 a temporary file is created from the image. On Unix, Pillow will no longer delete these
diff --git a/docs/releasenotes/9.3.0.rst b/docs/releasenotes/9.3.0.rst
index 7109a09f2..5a4086748 100644
--- a/docs/releasenotes/9.3.0.rst
+++ b/docs/releasenotes/9.3.0.rst
@@ -4,25 +4,6 @@
 Backwards Incompatible Changes
 ==============================
 
-TODO
-^^^^
-
-Deprecations
-============
-
-TODO
-^^^^
-
-TODO
-
-API Changes
-===========
-
-TODO
-^^^^
-
-TODO
-
 API Additions
 =============
 
@@ -55,15 +36,25 @@ Additional images can also be appended when saving, by combining the
 Security
 ========
 
-TODO
-^^^^
+Decode JPEG compressed BLP1 data in original mode
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
+Within the BLP image format, BLP1 data may use JPEG compression. Instead of
+telling the JPEG library that this data is in BGRX mode, Pillow will now
+decode the data in its natural CMYK mode, then convert it to RGB and rearrange
+the channels afterwards. Trying to load the data in an incorrect mode could
+result in a segmentation fault.
 
 Other Changes
 =============
 
-Added DDS ATI1 and ATI2 reading
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Added DDS ATI1, ATI2 and BC6H reading
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Support has been added to read the ATI1 and ATI2 formats of DDS images.
+Support has been added to read the ATI1, ATI2 and BC6H formats of DDS images.
+
+Show all frames with ImageShow
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When calling :py:meth:`~PIL.Image.Image.show` or using
+:py:mod:`~PIL.ImageShow`, all frames will now be shown.
diff --git a/setup.py b/setup.py
index aa3168aa5..14c404752 100755
--- a/setup.py
+++ b/setup.py
@@ -23,7 +23,7 @@ from setuptools.command.build_ext import build_ext
 
 def get_version():
     version_file = "src/PIL/_version.py"
-    with open(version_file) as f:
+    with open(version_file, encoding="utf-8") as f:
         exec(compile(f.read(), version_file, "exec"))
     return locals()["__version__"]
 
diff --git a/src/PIL/BlpImagePlugin.py b/src/PIL/BlpImagePlugin.py
index 104fbada9..533997737 100644
--- a/src/PIL/BlpImagePlugin.py
+++ b/src/PIL/BlpImagePlugin.py
@@ -373,8 +373,8 @@ class BLP1Decoder(_BLPBaseDecoder):
         data = BytesIO(data)
         image = JpegImageFile(data)
         Image._decompression_bomb_check(image.size)
-        image.mode = "RGB"
-        image.tile = [("jpeg", (0, 0) + self.size, 0, ("BGRX", ""))]
+        r, g, b = image.convert("RGB").split()
+        image = Image.merge("RGB", (b, g, r))
         self.set_as_raw(image.tobytes())
 
 
diff --git a/src/PIL/BmpImagePlugin.py b/src/PIL/BmpImagePlugin.py
index 8e69acd36..b8332062e 100644
--- a/src/PIL/BmpImagePlugin.py
+++ b/src/PIL/BmpImagePlugin.py
@@ -214,7 +214,7 @@ class BmpImageFile(ImageFile.ImageFile):
                     raw_mode, self.mode = "BGRA", "RGBA"
             except AttributeError:
                 pass
-        elif file_info["compression"] == self.RLE8:
+        elif file_info["compression"] in (self.RLE8, self.RLE4):
             decoder_name = "bmp_rle"
         else:
             raise OSError(f"Unsupported BMP compression ({file_info['compression']})")
@@ -253,16 +253,18 @@ class BmpImageFile(ImageFile.ImageFile):
 
         # ---------------------------- Finally set the tile data for the plugin
         self.info["compression"] = file_info["compression"]
+        args = [raw_mode]
+        if decoder_name == "bmp_rle":
+            args.append(file_info["compression"] == self.RLE4)
+        else:
+            args.append(((file_info["width"] * file_info["bits"] + 31) >> 3) & (~3))
+        args.append(file_info["direction"])
         self.tile = [
             (
                 decoder_name,
                 (0, 0, file_info["width"], file_info["height"]),
                 offset or self.fp.tell(),
-                (
-                    raw_mode,
-                    ((file_info["width"] * file_info["bits"] + 31) >> 3) & (~3),
-                    file_info["direction"],
-                ),
+                tuple(args),
             )
         ]
 
@@ -283,6 +285,7 @@ class BmpRleDecoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
     def decode(self, buffer):
+        rle4 = self.args[1]
         data = bytearray()
         x = 0
         while len(data) < self.state.xsize * self.state.ysize:
@@ -296,7 +299,16 @@ class BmpRleDecoder(ImageFile.PyDecoder):
                 if x + num_pixels > self.state.xsize:
                     # Too much data for row
                     num_pixels = max(0, self.state.xsize - x)
-                data += byte * num_pixels
+                if rle4:
+                    first_pixel = o8(byte[0] >> 4)
+                    second_pixel = o8(byte[0] & 0x0F)
+                    for index in range(num_pixels):
+                        if index % 2 == 0:
+                            data += first_pixel
+                        else:
+                            data += second_pixel
+                else:
+                    data += byte * num_pixels
                 x += num_pixels
             else:
                 if byte[0] == 0:
@@ -317,9 +329,18 @@ class BmpRleDecoder(ImageFile.PyDecoder):
                     x = len(data) % self.state.xsize
                 else:
                     # absolute mode
-                    bytes_read = self.fd.read(byte[0])
-                    data += bytes_read
-                    if len(bytes_read) < byte[0]:
+                    if rle4:
+                        # 2 pixels per byte
+                        byte_count = byte[0] // 2
+                        bytes_read = self.fd.read(byte_count)
+                        for byte_read in bytes_read:
+                            data += o8(byte_read >> 4)
+                            data += o8(byte_read & 0x0F)
+                    else:
+                        byte_count = byte[0]
+                        bytes_read = self.fd.read(byte_count)
+                        data += bytes_read
+                    if len(bytes_read) < byte_count:
                         break
                     x += byte[0]
 
diff --git a/src/PIL/DdsImagePlugin.py b/src/PIL/DdsImagePlugin.py
index bba480161..eea6e3153 100644
--- a/src/PIL/DdsImagePlugin.py
+++ b/src/PIL/DdsImagePlugin.py
@@ -101,6 +101,8 @@ DXGI_FORMAT_R8G8B8A8_UNORM_SRGB = 29
 DXGI_FORMAT_BC5_TYPELESS = 82
 DXGI_FORMAT_BC5_UNORM = 83
 DXGI_FORMAT_BC5_SNORM = 84
+DXGI_FORMAT_BC6H_UF16 = 95
+DXGI_FORMAT_BC6H_SF16 = 96
 DXGI_FORMAT_BC7_TYPELESS = 97
 DXGI_FORMAT_BC7_UNORM = 98
 DXGI_FORMAT_BC7_UNORM_SRGB = 99
@@ -181,6 +183,14 @@ class DdsImageFile(ImageFile.ImageFile):
                     self.pixel_format = "BC5S"
                     n = 5
                     self.mode = "RGB"
+                elif dxgi_format == DXGI_FORMAT_BC6H_UF16:
+                    self.pixel_format = "BC6H"
+                    n = 6
+                    self.mode = "RGB"
+                elif dxgi_format == DXGI_FORMAT_BC6H_SF16:
+                    self.pixel_format = "BC6HS"
+                    n = 6
+                    self.mode = "RGB"
                 elif dxgi_format in (DXGI_FORMAT_BC7_TYPELESS, DXGI_FORMAT_BC7_UNORM):
                     self.pixel_format = "BC7"
                     n = 7
diff --git a/src/PIL/FliImagePlugin.py b/src/PIL/FliImagePlugin.py
index e13b1779c..908bed9f4 100644
--- a/src/PIL/FliImagePlugin.py
+++ b/src/PIL/FliImagePlugin.py
@@ -15,6 +15,7 @@
 # See the README file for information on usage and redistribution.
 #
 
+import os
 
 from . import Image, ImageFile, ImagePalette
 from ._binary import i16le as i16
@@ -80,11 +81,19 @@ class FliImageFile(ImageFile.ImageFile):
 
         if i16(s, 4) == 0xF1FA:
             # look for palette chunk
-            s = self.fp.read(6)
-            if i16(s, 4) == 11:
-                self._palette(palette, 2)
-            elif i16(s, 4) == 4:
-                self._palette(palette, 0)
+            number_of_subchunks = i16(s, 6)
+            chunk_size = None
+            for _ in range(number_of_subchunks):
+                if chunk_size is not None:
+                    self.fp.seek(chunk_size - 6, os.SEEK_CUR)
+                s = self.fp.read(6)
+                chunk_type = i16(s, 4)
+                if chunk_type in (4, 11):
+                    self._palette(palette, 2 if chunk_type == 11 else 0)
+                    break
+                chunk_size = i32(s)
+                if not chunk_size:
+                    break
 
         palette = [o8(r) + o8(g) + o8(b) for (r, g, b) in palette]
         self.palette = ImagePalette.raw("RGB", b"".join(palette))
diff --git a/src/PIL/GifImagePlugin.py b/src/PIL/GifImagePlugin.py
index 20435fe31..dd1b21f2e 100644
--- a/src/PIL/GifImagePlugin.py
+++ b/src/PIL/GifImagePlugin.py
@@ -274,6 +274,8 @@ class GifImageFile(ImageFile.ImageFile):
                     p = self.fp.read(3 << bits)
                     if self._is_palette_needed(p):
                         palette = ImagePalette.raw("RGB", p)
+                    else:
+                        palette = False
 
                 # image data
                 bits = self.fp.read(1)[0]
@@ -298,12 +300,14 @@ class GifImageFile(ImageFile.ImageFile):
         if self.dispose:
             self.im.paste(self.dispose, self.dispose_extent)
 
-        self._frame_palette = palette or self.global_palette
+        self._frame_palette = palette if palette is not None else self.global_palette
+        self._frame_transparency = frame_transparency
         if frame == 0:
             if self._frame_palette:
-                self.mode = (
-                    "RGB" if LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS else "P"
-                )
+                if LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS:
+                    self.mode = "RGBA" if frame_transparency is not None else "RGB"
+                else:
+                    self.mode = "P"
             else:
                 self.mode = "L"
 
@@ -313,7 +317,6 @@ class GifImageFile(ImageFile.ImageFile):
                 palette = copy(self.global_palette)
             self.palette = palette
         else:
-            self._frame_transparency = frame_transparency
             if self.mode == "P":
                 if (
                     LOADING_STRATEGY != LoadingStrategy.RGB_AFTER_DIFFERENT_PALETTE_ONLY
@@ -386,7 +389,8 @@ class GifImageFile(ImageFile.ImageFile):
             transparency = -1
             if frame_transparency is not None:
                 if frame == 0:
-                    self.info["transparency"] = frame_transparency
+                    if LOADING_STRATEGY != LoadingStrategy.RGB_ALWAYS:
+                        self.info["transparency"] = frame_transparency
                 elif self.mode not in ("RGB", "RGBA"):
                     transparency = frame_transparency
             self.tile = [
@@ -410,9 +414,9 @@ class GifImageFile(ImageFile.ImageFile):
         temp_mode = "P" if self._frame_palette else "L"
         self._prev_im = None
         if self.__frame == 0:
-            if "transparency" in self.info:
+            if self._frame_transparency is not None:
                 self.im = Image.core.fill(
-                    temp_mode, self.size, self.info["transparency"]
+                    temp_mode, self.size, self._frame_transparency
                 )
         elif self.mode in ("RGB", "RGBA"):
             self._prev_im = self.im
@@ -429,19 +433,20 @@ class GifImageFile(ImageFile.ImageFile):
     def load_end(self):
         if self.__frame == 0:
             if self.mode == "P" and LOADING_STRATEGY == LoadingStrategy.RGB_ALWAYS:
-                self.mode = "RGB"
-                self.im = self.im.convert("RGB", Image.Dither.FLOYDSTEINBERG)
+                if self._frame_transparency is not None:
+                    self.im.putpalettealpha(self._frame_transparency, 0)
+                    self.mode = "RGBA"
+                else:
+                    self.mode = "RGB"
+                self.im = self.im.convert(self.mode, Image.Dither.FLOYDSTEINBERG)
             return
-        if self.mode == "P" and self._prev_im:
-            if self._frame_transparency is not None:
-                self.im.putpalettealpha(self._frame_transparency, 0)
-                frame_im = self.im.convert("RGBA")
-            else:
-                frame_im = self.im.convert("RGB")
+        if not self._prev_im:
+            return
+        if self._frame_transparency is not None:
+            self.im.putpalettealpha(self._frame_transparency, 0)
+            frame_im = self.im.convert("RGBA")
         else:
-            if not self._prev_im:
-                return
-            frame_im = self.im
+            frame_im = self.im.convert("RGB")
         frame_im = self._crop(frame_im, self.dispose_extent)
 
         self.im = self._prev_im
diff --git a/src/PIL/ImImagePlugin.py b/src/PIL/ImImagePlugin.py
index 78ccfb9cf..31b0ff469 100644
--- a/src/PIL/ImImagePlugin.py
+++ b/src/PIL/ImImagePlugin.py
@@ -352,7 +352,13 @@ def _save(im, fp, filename):
         fp.write(b"Lut: 1\r\n")
     fp.write(b"\000" * (511 - fp.tell()) + b"\032")
     if im.mode in ["P", "PA"]:
-        fp.write(im.im.getpalette("RGB", "RGB;L"))  # 768 bytes
+        im_palette = im.im.getpalette("RGB", "RGB;L")
+        colors = len(im_palette) // 3
+        palette = b""
+        for i in range(3):
+            palette += im_palette[colors * i : colors * (i + 1)]
+            palette += b"\x00" * (256 - colors)
+        fp.write(palette)  # 768 bytes
     ImageFile._save(im, fp, [("raw", (0, 0) + im.size, 0, (rawmode, 0, -1))])
 
 
diff --git a/src/PIL/Image.py b/src/PIL/Image.py
index 6611ceb3c..7faf0c248 100644
--- a/src/PIL/Image.py
+++ b/src/PIL/Image.py
@@ -679,12 +679,24 @@ class Image:
         new["shape"] = shape
         new["typestr"] = typestr
         new["version"] = 3
-        if self.mode == "1":
-            # Binary images need to be extended from bits to bytes
-            # See: https://github.com/python-pillow/Pillow/issues/350
-            new["data"] = self.tobytes("raw", "L")
-        else:
-            new["data"] = self.tobytes()
+        try:
+            if self.mode == "1":
+                # Binary images need to be extended from bits to bytes
+                # See: https://github.com/python-pillow/Pillow/issues/350
+                new["data"] = self.tobytes("raw", "L")
+            else:
+                new["data"] = self.tobytes()
+        except Exception as e:
+            if not isinstance(e, (MemoryError, RecursionError)):
+                try:
+                    import numpy
+                    from packaging.version import parse as parse_version
+                except ImportError:
+                    pass
+                else:
+                    if parse_version(numpy.__version__) < parse_version("1.23"):
+                        warnings.warn(e)
+            raise
         return new
 
     def __getstate__(self):
@@ -868,7 +880,7 @@ class Image:
         and the palette can be represented without a palette.
 
         The current version supports all possible conversions between
-        "L", "RGB" and "CMYK." The ``matrix`` argument only supports "L"
+        "L", "RGB" and "CMYK". The ``matrix`` argument only supports "L"
         and "RGB".
 
         When translating a color image to greyscale (mode "L"),
@@ -887,6 +899,9 @@ class Image:
         this passes the operation to :py:meth:`~PIL.Image.Image.quantize`,
         and ``dither`` and ``palette`` are ignored.
 
+        When converting from "PA", if an "RGBA" palette is present, the alpha
+        channel from the image will be used instead of the values from the palette.
+
         :param mode: The requested mode. See: :ref:`concept-modes`.
         :param matrix: An optional conversion matrix.  If given, this
            should be 4- or 12-tuple containing floating point values.
@@ -1027,6 +1042,19 @@ class Image:
                     warnings.warn("Couldn't allocate palette entry for transparency")
             return new
 
+        if "LAB" in (self.mode, mode):
+            other_mode = mode if self.mode == "LAB" else self.mode
+            if other_mode in ("RGB", "RGBA", "RGBX"):
+                from . import ImageCms
+
+                srgb = ImageCms.createProfile("sRGB")
+                lab = ImageCms.createProfile("LAB")
+                profiles = [lab, srgb] if self.mode == "LAB" else [srgb, lab]
+                transform = ImageCms.buildTransform(
+                    profiles[0], profiles[1], self.mode, mode
+                )
+                return transform.apply(self)
+
         # colorspace conversion
         if dither is None:
             dither = Dither.FLOYDSTEINBERG
@@ -1036,7 +1064,10 @@ class Image:
         except ValueError:
             try:
                 # normalize source image and try again
-                im = self.im.convert(getmodebase(self.mode))
+                modebase = getmodebase(self.mode)
+                if modebase == self.mode:
+                    raise
+                im = self.im.convert(modebase)
                 im = im.convert(mode, dither)
             except KeyError as e:
                 raise ValueError("illegal conversion") from e
diff --git a/src/PIL/ImageDraw.py b/src/PIL/ImageDraw.py
index e84dafb12..3a6063a6c 100644
--- a/src/PIL/ImageDraw.py
+++ b/src/PIL/ImageDraw.py
@@ -482,8 +482,8 @@ class ImageDraw:
                 # extract mask and set text alpha
                 color, mask = mask, mask.getband(3)
                 color.fillband(3, (ink >> 24) & 0xFF)
-                coord2 = coord[0] + mask.size[0], coord[1] + mask.size[1]
-                self.im.paste(color, coord + coord2, mask)
+                x, y = (int(c) for c in coord)
+                self.im.paste(color, (x, y, x + mask.size[0], y + mask.size[1]), mask)
             else:
                 self.draw.draw_bitmap(coord, mask, ink)
 
diff --git a/src/PIL/ImageFont.py b/src/PIL/ImageFont.py
index 8be7f0f10..b3a7cdb98 100644
--- a/src/PIL/ImageFont.py
+++ b/src/PIL/ImageFont.py
@@ -955,6 +955,11 @@ def truetype(font=None, size=10, index=0, encoding="", layout_engine=None):
                      encoding of any text provided in subsequent operations.
     :param layout_engine: Which layout engine to use, if available:
                      :data:`.ImageFont.Layout.BASIC` or :data:`.ImageFont.Layout.RAQM`.
+                     If it is available, Raqm layout will be used by default.
+                     Otherwise, basic layout will be used.
+
+                     Raqm layout is recommended for all non-English text. If Raqm layout
+                     is not required, basic layout will have better performance.
 
                      You can check support for Raqm layout using
                      :py:func:`PIL.features.check_feature` with ``feature="raqm"``.
diff --git a/src/PIL/ImagePalette.py b/src/PIL/ImagePalette.py
index b73b2cd9d..fe76c86f4 100644
--- a/src/PIL/ImagePalette.py
+++ b/src/PIL/ImagePalette.py
@@ -115,7 +115,11 @@ class ImagePalette:
             raise ValueError("palette contains raw palette data")
         if isinstance(color, tuple):
             if self.mode == "RGB":
-                if len(color) == 4 and color[3] == 255:
+                if len(color) == 4:
+                    if color[3] != 255:
+                        raise ValueError(
+                            "cannot add non-opaque RGBA color to RGB palette"
+                        )
                     color = color[:3]
             elif self.mode == "RGBA":
                 if len(color) == 3:
diff --git a/src/PIL/ImageShow.py b/src/PIL/ImageShow.py
index 9f9a551fb..76f42a307 100644
--- a/src/PIL/ImageShow.py
+++ b/src/PIL/ImageShow.py
@@ -136,7 +136,7 @@ class WindowsViewer(Viewer):
     """The default viewer on Windows is the default system application for PNG files."""
 
     format = "PNG"
-    options = {"compress_level": 1}
+    options = {"compress_level": 1, "save_all": True}
 
     def get_command(self, file, **options):
         return (
@@ -154,7 +154,7 @@ class MacViewer(Viewer):
     """The default viewer on macOS using ``Preview.app``."""
 
     format = "PNG"
-    options = {"compress_level": 1}
+    options = {"compress_level": 1, "save_all": True}
 
     def get_command(self, file, **options):
         # on darwin open returns immediately resulting in the temp
@@ -197,7 +197,7 @@ if sys.platform == "darwin":
 
 class UnixViewer(Viewer):
     format = "PNG"
-    options = {"compress_level": 1}
+    options = {"compress_level": 1, "save_all": True}
 
     def get_command(self, file, **options):
         command = self.get_command_ex(file, **options)[0]
diff --git a/src/PIL/ImtImagePlugin.py b/src/PIL/ImtImagePlugin.py
index 5790acdaf..dc7078012 100644
--- a/src/PIL/ImtImagePlugin.py
+++ b/src/PIL/ImtImagePlugin.py
@@ -39,15 +39,19 @@ class ImtImageFile(ImageFile.ImageFile):
         # Quick rejection: if there's not a LF among the first
         # 100 bytes, this is (probably) not a text header.
 
-        if b"\n" not in self.fp.read(100):
+        buffer = self.fp.read(100)
+        if b"\n" not in buffer:
             raise SyntaxError("not an IM file")
-        self.fp.seek(0)
 
         xsize = ysize = 0
 
         while True:
 
-            s = self.fp.read(1)
+            if buffer:
+                s = buffer[:1]
+                buffer = buffer[1:]
+            else:
+                s = self.fp.read(1)
             if not s:
                 break
 
@@ -55,7 +59,12 @@ class ImtImageFile(ImageFile.ImageFile):
 
                 # image data begins
                 self.tile = [
-                    ("raw", (0, 0) + self.size, self.fp.tell(), (self.mode, 0, 1))
+                    (
+                        "raw",
+                        (0, 0) + self.size,
+                        self.fp.tell() - len(buffer),
+                        (self.mode, 0, 1),
+                    )
                 ]
 
                 break
@@ -63,8 +72,11 @@ class ImtImageFile(ImageFile.ImageFile):
             else:
 
                 # read key/value pair
-                # FIXME: dangerous, may read whole file
-                s = s + self.fp.readline()
+                if b"\n" not in buffer:
+                    buffer += self.fp.read(100)
+                lines = buffer.split(b"\n")
+                s += lines.pop(0)
+                buffer = b"\n".join(lines)
                 if len(s) == 1 or len(s) > 100:
                     break
                 if s[0] == ord(b"*"):
@@ -74,13 +86,13 @@ class ImtImageFile(ImageFile.ImageFile):
                 if not m:
                     break
                 k, v = m.group(1, 2)
-                if k == "width":
+                if k == b"width":
                     xsize = int(v)
                     self._size = xsize, ysize
-                elif k == "height":
+                elif k == b"height":
                     ysize = int(v)
                     self._size = xsize, ysize
-                elif k == "pixel" and v == "n8":
+                elif k == b"pixel" and v == b"n8":
                     self.mode = "L"
 
 
diff --git a/src/PIL/PngImagePlugin.py b/src/PIL/PngImagePlugin.py
index 442c65e6f..7fb468877 100644
--- a/src/PIL/PngImagePlugin.py
+++ b/src/PIL/PngImagePlugin.py
@@ -189,7 +189,7 @@ class ChunkStream:
         self.close()
 
     def close(self):
-        self.queue = self.crc = self.fp = None
+        self.queue = self.fp = None
 
     def push(self, cid, pos, length):
 
@@ -224,7 +224,7 @@ class ChunkStream:
             ) from e
 
     def crc_skip(self, cid, data):
-        """Read checksum.  Used if the C module is not present"""
+        """Read checksum"""
 
         self.fp.read(4)
 
@@ -1089,28 +1089,28 @@ class _fdat:
         self.seq_num += 1
 
 
-def _write_multiple_frames(im, fp, chunk, rawmode):
-    default_image = im.encoderinfo.get("default_image", im.info.get("default_image"))
+def _write_multiple_frames(im, fp, chunk, rawmode, default_image, append_images):
     duration = im.encoderinfo.get("duration", im.info.get("duration", 0))
     loop = im.encoderinfo.get("loop", im.info.get("loop", 0))
     disposal = im.encoderinfo.get("disposal", im.info.get("disposal", Disposal.OP_NONE))
     blend = im.encoderinfo.get("blend", im.info.get("blend", Blend.OP_SOURCE))
 
     if default_image:
-        chain = itertools.chain(im.encoderinfo.get("append_images", []))
+        chain = itertools.chain(append_images)
     else:
-        chain = itertools.chain([im], im.encoderinfo.get("append_images", []))
+        chain = itertools.chain([im], append_images)
 
     im_frames = []
     frame_count = 0
     for im_seq in chain:
         for im_frame in ImageSequence.Iterator(im_seq):
-            im_frame = im_frame.copy()
-            if im_frame.mode != im.mode:
-                if im.mode == "P":
-                    im_frame = im_frame.convert(im.mode, palette=im.palette)
+            if im_frame.mode == rawmode:
+                im_frame = im_frame.copy()
+            else:
+                if rawmode == "P":
+                    im_frame = im_frame.convert(rawmode, palette=im.palette)
                 else:
-                    im_frame = im_frame.convert(im.mode)
+                    im_frame = im_frame.convert(rawmode)
             encoderinfo = im.encoderinfo.copy()
             if isinstance(duration, (list, tuple)):
                 encoderinfo["duration"] = duration[frame_count]
@@ -1221,7 +1221,26 @@ def _save_all(im, fp, filename):
 def _save(im, fp, filename, chunk=putchunk, save_all=False):
     # save an image to disk (called by the save method)
 
-    mode = im.mode
+    if save_all:
+        default_image = im.encoderinfo.get(
+            "default_image", im.info.get("default_image")
+        )
+        modes = set()
+        append_images = im.encoderinfo.get("append_images", [])
+        if default_image:
+            chain = itertools.chain(append_images)
+        else:
+            chain = itertools.chain([im], append_images)
+        for im_seq in chain:
+            for im_frame in ImageSequence.Iterator(im_seq):
+                modes.add(im_frame.mode)
+        for mode in ("RGBA", "RGB", "P"):
+            if mode in modes:
+                break
+        else:
+            mode = modes.pop()
+    else:
+        mode = im.mode
 
     if mode == "P":
 
@@ -1373,7 +1392,7 @@ def _save(im, fp, filename, chunk=putchunk, save_all=False):
         chunk(fp, b"eXIf", exif)
 
     if save_all:
-        _write_multiple_frames(im, fp, chunk, rawmode)
+        _write_multiple_frames(im, fp, chunk, rawmode, default_image, append_images)
     else:
         ImageFile._save(im, _idat(fp, chunk), [("zip", (0, 0) + im.size, 0, rawmode)])
 
diff --git a/src/PIL/TiffImagePlugin.py b/src/PIL/TiffImagePlugin.py
index 766d46ffb..04a63bd2b 100644
--- a/src/PIL/TiffImagePlugin.py
+++ b/src/PIL/TiffImagePlugin.py
@@ -173,6 +173,7 @@ OPEN_INFO = {
     (II, 1, (1,), 2, (8,), ()): ("L", "L;R"),
     (MM, 1, (1,), 2, (8,), ()): ("L", "L;R"),
     (II, 1, (1,), 1, (12,), ()): ("I;16", "I;12"),
+    (II, 0, (1,), 1, (16,), ()): ("I;16", "I;16"),
     (II, 1, (1,), 1, (16,), ()): ("I;16", "I;16"),
     (MM, 1, (1,), 1, (16,), ()): ("I;16B", "I;16B"),
     (II, 1, (1,), 2, (16,), ()): ("I;16", "I;16R"),
diff --git a/src/PIL/TiffTags.py b/src/PIL/TiffTags.py
index 3f3a1ccd2..9b5277138 100644
--- a/src/PIL/TiffTags.py
+++ b/src/PIL/TiffTags.py
@@ -232,7 +232,39 @@ TAGS_V2_GROUPS = {
         41730: ("CFAPattern", UNDEFINED, 1),
     },
     # GPSInfoIFD
-    34853: {},
+    34853: {
+        0: ("GPSVersionID", BYTE, 4),
+        1: ("GPSLatitudeRef", ASCII, 2),
+        2: ("GPSLatitude", RATIONAL, 3),
+        3: ("GPSLongitudeRef", ASCII, 2),
+        4: ("GPSLongitude", RATIONAL, 3),
+        5: ("GPSAltitudeRef", BYTE, 1),
+        6: ("GPSAltitude", RATIONAL, 1),
+        7: ("GPSTimeStamp", RATIONAL, 3),
+        8: ("GPSSatellites", ASCII, 0),
+        9: ("GPSStatus", ASCII, 2),
+        10: ("GPSMeasureMode", ASCII, 2),
+        11: ("GPSDOP", RATIONAL, 1),
+        12: ("GPSSpeedRef", ASCII, 2),
+        13: ("GPSSpeed", RATIONAL, 1),
+        14: ("GPSTrackRef", ASCII, 2),
+        15: ("GPSTrack", RATIONAL, 1),
+        16: ("GPSImgDirectionRef", ASCII, 2),
+        17: ("GPSImgDirection", RATIONAL, 1),
+        18: ("GPSMapDatum", ASCII, 0),
+        19: ("GPSDestLatitudeRef", ASCII, 2),
+        20: ("GPSDestLatitude", RATIONAL, 3),
+        21: ("GPSDestLongitudeRef", ASCII, 2),
+        22: ("GPSDestLongitude", RATIONAL, 3),
+        23: ("GPSDestBearingRef", ASCII, 2),
+        24: ("GPSDestBearing", RATIONAL, 1),
+        25: ("GPSDestDistanceRef", ASCII, 2),
+        26: ("GPSDestDistance", RATIONAL, 1),
+        27: ("GPSProcessingMethod", UNDEFINED, 0),
+        28: ("GPSAreaInformation", UNDEFINED, 0),
+        29: ("GPSDateStamp", ASCII, 11),
+        30: ("GPSDifferential", SHORT, 1),
+    },
     # InteroperabilityIFD
     40965: {1: ("InteropIndex", ASCII, 1), 2: ("InteropVersion", UNDEFINED, 1)},
 }
diff --git a/src/PIL/WebPImagePlugin.py b/src/PIL/WebPImagePlugin.py
index c1f4b730f..5eaeb10cc 100644
--- a/src/PIL/WebPImagePlugin.py
+++ b/src/PIL/WebPImagePlugin.py
@@ -311,9 +311,11 @@ def _save(im, fp, filename):
     lossless = im.encoderinfo.get("lossless", False)
     quality = im.encoderinfo.get("quality", 80)
     icc_profile = im.encoderinfo.get("icc_profile") or ""
-    exif = im.encoderinfo.get("exif", "")
+    exif = im.encoderinfo.get("exif", b"")
     if isinstance(exif, Image.Exif):
         exif = exif.tobytes()
+    if exif.startswith(b"Exif\x00\x00"):
+        exif = exif[6:]
     xmp = im.encoderinfo.get("xmp", "")
     method = im.encoderinfo.get("method", 4)
 
diff --git a/src/decode.c b/src/decode.c
index cb018a4e7..7a9b956c5 100644
--- a/src/decode.c
+++ b/src/decode.c
@@ -376,11 +376,8 @@ PyImaging_BcnDecoderNew(PyObject *self, PyObject *args) {
             actual = "L";
             break;
         case 5: /* BC5: 2-channel 8-bit via 2 BC3 alpha blocks */
-            actual = "RGB";
-            break;
         case 6: /* BC6: 3-channel 16-bit float */
-            /* TODO: support 4-channel floating point images */
-            actual = "RGBAF";
+            actual = "RGB";
             break;
         default:
             PyErr_SetString(PyExc_ValueError, "block compression type unknown");
diff --git a/src/libImaging/BcnDecode.c b/src/libImaging/BcnDecode.c
index 22b36eb7a..a57b74b61 100644
--- a/src/libImaging/BcnDecode.c
+++ b/src/libImaging/BcnDecode.c
@@ -23,10 +23,6 @@ typedef struct {
     UINT8 l;
 } lum;
 
-typedef struct {
-    FLOAT32 r, g, b;
-} rgb32f;
-
 typedef struct {
     UINT16 c0, c1;
     UINT32 lut;
@@ -536,53 +532,53 @@ static const bc6_mode_info bc6_modes[] = {
 
 /* Table.F, encoded as a sequence of bit indices */
 static const UINT8 bc6_bit_packings[][75] = {
-    {116, 132, 176, 0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   16,  17,
+    {116, 132, 180, 0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   16,  17,
      18,  19,  20,  21,  22,  23,  24,  25,  32,  33,  34,  35,  36,  37,  38,
      39,  40,  41,  48,  49,  50,  51,  52,  164, 112, 113, 114, 115, 64,  65,
-     66,  67,  68,  172, 160, 161, 162, 163, 80,  81,  82,  83,  84,  173, 128,
-     129, 130, 131, 96,  97,  98,  99,  100, 174, 144, 145, 146, 147, 148, 175},
-    {117, 164, 165, 0,  1,   2,   3,   4,   5,   6,   172, 173, 132, 16,  17,
-     18,  19,  20,  21, 22,  133, 174, 116, 32,  33,  34,  35,  36,  37,  38,
-     175, 177, 176, 48, 49,  50,  51,  52,  53,  112, 113, 114, 115, 64,  65,
+     66,  67,  68,  176, 160, 161, 162, 163, 80,  81,  82,  83,  84,  177, 128,
+     129, 130, 131, 96,  97,  98,  99,  100, 178, 144, 145, 146, 147, 148, 179},
+    {117, 164, 165, 0,  1,   2,   3,   4,   5,   6,   176, 177, 132, 16,  17,
+     18,  19,  20,  21, 22,  133, 178, 116, 32,  33,  34,  35,  36,  37,  38,
+     179, 181, 180, 48, 49,  50,  51,  52,  53,  112, 113, 114, 115, 64,  65,
      66,  67,  68,  69, 160, 161, 162, 163, 80,  81,  82,  83,  84,  85,  128,
      129, 130, 131, 96, 97,  98,  99,  100, 101, 144, 145, 146, 147, 148, 149},
     {0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   16,  17,  18,  19,  20,
      21,  22,  23,  24,  25,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,
      48,  49,  50,  51,  52,  10,  112, 113, 114, 115, 64,  65,  66,  67,  26,
-     172, 160, 161, 162, 163, 80,  81,  82,  83,  42,  173, 128, 129, 130, 131,
-     96,  97,  98,  99,  100, 174, 144, 145, 146, 147, 148, 175},
+     176, 160, 161, 162, 163, 80,  81,  82,  83,  42,  177, 128, 129, 130, 131,
+     96,  97, 98,  99,  100, 178, 144, 145, 146, 147, 148, 179},
     {0,  1,   2,   3,   4,   5,   6,   7,   8,   9,   16,  17,  18,  19,  20,
      21, 22,  23,  24,  25,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,
      48, 49,  50,  51,  10,  164, 112, 113, 114, 115, 64,  65,  66,  67,  68,
-     26, 160, 161, 162, 163, 80,  81,  82,  83,  42,  173, 128, 129, 130, 131,
-     96, 97,  98,  99,  172, 174, 144, 145, 146, 147, 116, 175},
+     26, 160, 161, 162, 163, 80,  81,  82,  83,  42,  177, 128, 129, 130, 131,
+     96, 97,  98,  99,  176, 178, 144, 145, 146, 147, 116, 179},
     {0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   16,  17,  18,  19,  20,
      21,  22,  23,  24,  25,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,
      48,  49,  50,  51,  10,  132, 112, 113, 114, 115, 64,  65,  66,  67,  26,
-     172, 160, 161, 162, 163, 80,  81,  82,  83,  84,  42,  128, 129, 130, 131,
-     96,  97,  98,  99,  173, 174, 144, 145, 146, 147, 176, 175},
+     176, 160, 161, 162, 163, 80,  81,  82,  83,  84,  42,  128, 129, 130, 131,
+     96,  97,  98,  99,  177, 178, 144, 145, 146, 147, 180, 179},
     {0,   1,   2,   3,   4,   5,   6,   7,   8,   132, 16,  17,  18,  19,  20,
-     21,  22,  23,  24,  116, 32,  33,  34,  35,  36,  37,  38,  39,  40,  176,
+     21,  22,  23,  24,  116, 32,  33,  34,  35,  36,  37,  38,  39,  40,  180,
      48,  49,  50,  51,  52,  164, 112, 113, 114, 115, 64,  65,  66,  67,  68,
-     172, 160, 161, 162, 163, 80,  81,  82,  83,  84,  173, 128, 129, 130, 131,
-     96,  97,  98,  99,  100, 174, 144, 145, 146, 147, 148, 175},
+     176, 160, 161, 162, 163, 80,  81,  82,  83,  84,  177, 128, 129, 130, 131,
+     96,  97,  98,  99,  100, 178, 144, 145, 146, 147, 148, 179},
     {0,   1,   2,   3,   4,   5,   6,   7,   164, 132, 16,  17,  18,  19,  20,
-     21,  22,  23,  174, 116, 32,  33,  34,  35,  36,  37,  38,  39,  175, 176,
+     21,  22,  23,  178, 116, 32,  33,  34,  35,  36,  37,  38,  39,  179, 180,
      48,  49,  50,  51,  52,  53,  112, 113, 114, 115, 64,  65,  66,  67,  68,
-     172, 160, 161, 162, 163, 80,  81,  82,  83,  84,  173, 128, 129, 130, 131,
+     176, 160, 161, 162, 163, 80,  81,  82,  83,  84,  177, 128, 129, 130, 131,
      96,  97,  98,  99,  100, 101, 144, 145, 146, 147, 148, 149},
-    {0,  1,   2,   3,   4,   5,   6,   7,   172, 132, 16,  17,  18,  19,  20,
-     21, 22,  23,  117, 116, 32,  33,  34,  35,  36,  37,  38,  39,  165, 176,
+    {0,  1,   2,   3,   4,   5,   6,   7,   176, 132, 16,  17,  18,  19,  20,
+     21, 22,  23,  117, 116, 32,  33,  34,  35,  36,  37,  38,  39,  165, 180,
      48, 49,  50,  51,  52,  164, 112, 113, 114, 115, 64,  65,  66,  67,  68,
-     69, 160, 161, 162, 163, 80,  81,  82,  83,  84,  173, 128, 129, 130, 131,
-     96, 97,  98,  99,  100, 174, 144, 145, 146, 147, 148, 175},
-    {0,   1,   2,   3,   4,   5,   6,   7,   173, 132, 16,  17,  18,  19,  20,
-     21,  22,  23,  133, 116, 32,  33,  34,  35,  36,  37,  38,  39,  177, 176,
+     69, 160, 161, 162, 163, 80,  81,  82,  83,  84,  177, 128, 129, 130, 131,
+     96, 97,  98,  99,  100, 178, 144, 145, 146, 147, 148, 179},
+    {0,   1,   2,   3,   4,   5,   6,   7,   177, 132, 16,  17,  18,  19,  20,
+     21,  22,  23,  133, 116, 32,  33,  34,  35,  36,  37,  38,  39,  181, 180,
      48,  49,  50,  51,  52,  164, 112, 113, 114, 115, 64,  65,  66,  67,  68,
-     172, 160, 161, 162, 163, 80,  81,  82,  83,  84,  85,  128, 129, 130, 131,
-     96,  97,  98,  99,  100, 174, 144, 145, 146, 147, 148, 175},
-    {0,  1,   2,   3,   4,   5,   164, 172, 173, 132, 16,  17,  18,  19,  20,
-     21, 117, 133, 174, 116, 32,  33,  34,  35,  36,  37,  165, 175, 177, 176,
+     176, 160, 161, 162, 163, 80,  81,  82,  83,  84,  85,  128, 129, 130, 131,
+     96,  97,  98,  99,  100, 178, 144, 145, 146, 147, 148, 179},
+    {0,  1,   2,   3,   4,   5,   164, 176, 177, 132, 16,  17,  18,  19,  20,
+     21, 117, 133, 178, 116, 32,  33,  34,  35,  36,  37,  165, 179, 181, 180,
      48, 49,  50,  51,  52,  53,  112, 113, 114, 115, 64,  65,  66,  67,  68,
      69, 160, 161, 162, 163, 80,  81,  82,  83,  84,  85,  128, 129, 130, 131,
      96, 97,  98,  99,  100, 101, 144, 145, 146, 147, 148, 149},
@@ -681,20 +677,31 @@ bc6_finalize(int v, int sign) {
     }
 }
 
+static UINT8
+bc6_clamp(float value) {
+    if (value < 0.0f) {
+        return 0;
+    } else if (value > 1.0f) {
+        return 255;
+    } else {
+        return (UINT8) (value * 255.0f);
+    }
+}
+
 static void
-bc6_lerp(rgb32f *col, int *e0, int *e1, int s, int sign) {
+bc6_lerp(rgba *col, int *e0, int *e1, int s, int sign) {
     int r, g, b;
     int t = 64 - s;
     r = (e0[0] * t + e1[0] * s) >> 6;
     g = (e0[1] * t + e1[1] * s) >> 6;
     b = (e0[2] * t + e1[2] * s) >> 6;
-    col->r = bc6_finalize(r, sign);
-    col->g = bc6_finalize(g, sign);
-    col->b = bc6_finalize(b, sign);
+    col->r = bc6_clamp(bc6_finalize(r, sign));
+    col->g = bc6_clamp(bc6_finalize(g, sign));
+    col->b = bc6_clamp(bc6_finalize(b, sign));
 }
 
 static void
-decode_bc6_block(rgb32f *col, const UINT8 *src, int sign) {
+decode_bc6_block(rgba *col, const UINT8 *src, int sign) {
     UINT16 endpoints[12]; /* storage for r0, g0, b0, r1, ... */
     int ueps[12];
     int i, i0, ib2, di, dw, mask, numep, s;
@@ -744,21 +751,16 @@ decode_bc6_block(rgb32f *col, const UINT8 *src, int sign) {
     }
     if (sign || info->tr) { /* sign-extend e1,2,3 if signed or deltas */
         for (i = 3; i < numep; i += 3) {
-            bc6_sign_extend(&endpoints[i + 0], info->rb);
+            bc6_sign_extend(&endpoints[i], info->rb);
             bc6_sign_extend(&endpoints[i + 1], info->gb);
             bc6_sign_extend(&endpoints[i + 2], info->bb);
         }
     }
     if (info->tr) { /* apply deltas */
-        for (i = 3; i < numep; i++) {
+        for (i = 3; i < numep; i += 3) {
             endpoints[i] = (endpoints[i] + endpoints[0]) & mask;
-        }
-        if (sign) {
-            for (i = 3; i < numep; i += 3) {
-                bc6_sign_extend(&endpoints[i + 0], info->rb);
-                bc6_sign_extend(&endpoints[i + 1], info->gb);
-                bc6_sign_extend(&endpoints[i + 2], info->bb);
-            }
+            endpoints[i + 1] = (endpoints[i + 1] + endpoints[1]) & mask;
+            endpoints[i + 2] = (endpoints[i + 2] + endpoints[2]) & mask;
         }
     }
     for (i = 0; i < numep; i++) {
@@ -862,8 +864,8 @@ decode_bcn(
             break;
         case 6:
             while (bytes >= 16) {
-                rgb32f col[16];
-                decode_bc6_block(col, ptr, (state->state >> 4) & 1);
+                rgba col[16];
+                decode_bc6_block(col, ptr, strcmp(pixel_format, "BC6HS") == 0 ? 1 : 0);
                 put_block(im, state, (const char *)col, sizeof(col[0]), C);
                 ptr += 16;
                 bytes -= 16;
diff --git a/src/libImaging/Paste.c b/src/libImaging/Paste.c
index fafd8141e..acf5202e5 100644
--- a/src/libImaging/Paste.c
+++ b/src/libImaging/Paste.c
@@ -432,18 +432,18 @@ fill_mask_L(
         }
 
     } else {
+        int alpha_channel = strcmp(imOut->mode, "RGBa") == 0 ||
+                            strcmp(imOut->mode, "RGBA") == 0 ||
+                            strcmp(imOut->mode, "La") == 0 ||
+                            strcmp(imOut->mode, "LA") == 0 ||
+                            strcmp(imOut->mode, "PA") == 0;
         for (y = 0; y < ysize; y++) {
             UINT8 *out = (UINT8 *)imOut->image[y + dy] + dx * pixelsize;
             UINT8 *mask = (UINT8 *)imMask->image[y + sy] + sx;
             for (x = 0; x < xsize; x++) {
                 for (i = 0; i < pixelsize; i++) {
                     UINT8 channel_mask = *mask;
-                    if ((strcmp(imOut->mode, "RGBa") == 0 ||
-                         strcmp(imOut->mode, "RGBA") == 0 ||
-                         strcmp(imOut->mode, "La") == 0 ||
-                         strcmp(imOut->mode, "LA") == 0 ||
-                         strcmp(imOut->mode, "PA") == 0) &&
-                        i != 3 && channel_mask != 0) {
+                    if (alpha_channel && i != 3 && channel_mask != 0) {
                         channel_mask =
                             255 - (255 - channel_mask) * (1 - (255 - out[3]) / 255);
                     }
diff --git a/winbuild/build_prepare.py b/winbuild/build_prepare.py
index f4515468f..f4858b630 100644
--- a/winbuild/build_prepare.py
+++ b/winbuild/build_prepare.py
@@ -132,9 +132,9 @@ deps = {
         "bins": ["cjpeg.exe", "djpeg.exe"],
     },
     "zlib": {
-        "url": "https://zlib.net/zlib1212.zip",
-        "filename": "zlib1212.zip",
-        "dir": "zlib-1.2.12",
+        "url": "https://zlib.net/zlib1213.zip",
+        "filename": "zlib1213.zip",
+        "dir": "zlib-1.2.13",
         "build": [
             cmd_nmake(r"win32\Makefile.msc", "clean"),
             cmd_nmake(r"win32\Makefile.msc", "zlib.lib"),
@@ -281,9 +281,9 @@ deps = {
         "libs": [r"imagequant.lib"],
     },
     "harfbuzz": {
-        "url": "https://github.com/harfbuzz/harfbuzz/archive/5.2.0.zip",
-        "filename": "harfbuzz-5.2.0.zip",
-        "dir": "harfbuzz-5.2.0",
+        "url": "https://github.com/harfbuzz/harfbuzz/archive/5.3.1.zip",
+        "filename": "harfbuzz-5.3.1.zip",
+        "dir": "harfbuzz-5.3.1",
         "build": [
             cmd_cmake("-DHB_HAVE_FREETYPE:BOOL=TRUE"),
             cmd_nmake(target="clean"),