diff --git a/Tests/test_features.py b/Tests/test_features.py
index d11a31ce3..93d803fc1 100644
--- a/Tests/test_features.py
+++ b/Tests/test_features.py
@@ -21,11 +21,7 @@ def test_check() -> None:
     for codec in features.codecs:
         assert features.check_codec(codec) == features.check(codec)
     for feature in features.features:
-        if "webp" in feature:
-            with pytest.warns(DeprecationWarning, match="webp"):
-                assert features.check_feature(feature) == features.check(feature)
-        else:
-            assert features.check_feature(feature) == features.check(feature)
+        assert features.check_feature(feature) == features.check(feature)
 
 
 def test_version() -> None:
@@ -51,11 +47,7 @@ def test_version() -> None:
     for codec in features.codecs:
         test(codec, features.version_codec)
     for feature in features.features:
-        if "webp" in feature:
-            with pytest.warns(DeprecationWarning, match="webp"):
-                test(feature, features.version_feature)
-        else:
-            test(feature, features.version_feature)
+        test(feature, features.version_feature)
 
 
 @skip_unless_feature("libjpeg_turbo")
@@ -115,6 +107,25 @@ def test_unsupported_module() -> None:
         features.version_module(module)
 
 
+def test_unsupported_feature() -> None:
+    # Arrange
+    feature = "unsupported_feature"
+    # Act / Assert
+    with pytest.raises(ValueError):
+        features.check_feature(feature)
+    with pytest.raises(ValueError):
+        features.version_feature(feature)
+
+
+def test_unsupported_version() -> None:
+    assert features.version("unsupported_version") is None
+
+
+def test_modulenotfound(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setattr(features, "features", {"test": ("PIL._test", "", "")})
+    assert features.check_feature("test") is None
+
+
 @pytest.mark.parametrize("supported_formats", (True, False))
 def test_pilinfo(supported_formats: bool) -> None:
     buf = io.StringIO()
diff --git a/Tests/test_image_access.py b/Tests/test_image_access.py
index a847264d2..07c12594a 100644
--- a/Tests/test_image_access.py
+++ b/Tests/test_image_access.py
@@ -317,4 +317,8 @@ int main(int argc, char* argv[])
         assert process.returncode == 0
 
     def teardown_method(self) -> None:
-        os.remove("embed_pil.c")
+        try:
+            os.remove("embed_pil.c")
+        except FileNotFoundError:
+            # If the test was skipped or failed, the file won't exist
+            pass
diff --git a/Tests/test_image_histogram.py b/Tests/test_image_histogram.py
index dbd55d4c2..436eb78a2 100644
--- a/Tests/test_image_histogram.py
+++ b/Tests/test_image_histogram.py
@@ -10,9 +10,12 @@ def test_histogram() -> None:
 
     assert histogram("1") == (256, 0, 10994)
     assert histogram("L") == (256, 0, 662)
+    assert histogram("LA") == (512, 0, 16384)
+    assert histogram("La") == (512, 0, 16384)
     assert histogram("I") == (256, 0, 662)
     assert histogram("F") == (256, 0, 662)
     assert histogram("P") == (256, 0, 1551)
+    assert histogram("PA") == (512, 0, 16384)
     assert histogram("RGB") == (768, 4, 675)
     assert histogram("RGBA") == (1024, 0, 16384)
     assert histogram("CMYK") == (1024, 0, 16384)
diff --git a/Tests/test_pyroma.py b/Tests/test_pyroma.py
index c2f7fe22e..35f3fd076 100644
--- a/Tests/test_pyroma.py
+++ b/Tests/test_pyroma.py
@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+from importlib.metadata import metadata
+
 import pytest
 
 from PIL import __version__
@@ -7,9 +9,30 @@ from PIL import __version__
 pyroma = pytest.importorskip("pyroma", reason="Pyroma not installed")
 
 
+def map_metadata_keys(metadata):
+    # Convert installed wheel metadata into canonical Core Metadata 2.4 format.
+    # This was a utility method in pyroma 4.3.3; it was removed in 5.0.
+    # This implementation is constructed from the relevant logic from
+    # Pyroma 5.0's `build_metadata()` implementation. This has been submitted
+    # upstream to Pyroma as https://github.com/regebro/pyroma/pull/116,
+    # so it may be possible to simplify this test in future.
+    data = {}
+    for key in set(metadata.keys()):
+        value = metadata.get_all(key)
+        key = pyroma.projectdata.normalize(key)
+
+        if len(value) == 1:
+            value = value[0]
+            if value.strip() == "UNKNOWN":
+                continue
+
+        data[key] = value
+    return data
+
+
 def test_pyroma() -> None:
     # Arrange
-    data = pyroma.projectdata.get_data(".")
+    data = map_metadata_keys(metadata("Pillow"))
 
     # Act
     rating = pyroma.ratings.rate(data)
diff --git a/pyproject.toml b/pyproject.toml
index 7c4438840..a9d7ea031 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -67,7 +67,7 @@ optional-dependencies.tests = [
   "markdown2",
   "olefile",
   "packaging",
-  "pyroma",
+  "pyroma>=5",
   "pytest",
   "pytest-cov",
   "pytest-timeout",
diff --git a/src/libImaging/Histo.c b/src/libImaging/Histo.c
index c5a547a64..87c09d3d4 100644
--- a/src/libImaging/Histo.c
+++ b/src/libImaging/Histo.c
@@ -132,11 +132,15 @@ ImagingGetHistogram(Imaging im, Imaging imMask, void *minmax) {
                     ImagingSectionEnter(&cookie);
                     for (y = 0; y < im->ysize; y++) {
                         UINT8 *in = (UINT8 *)im->image[y];
-                        for (x = 0; x < im->xsize; x++) {
-                            h->histogram[(*in++)]++;
-                            h->histogram[(*in++) + 256]++;
-                            h->histogram[(*in++) + 512]++;
-                            h->histogram[(*in++) + 768]++;
+                        for (x = 0; x < im->xsize; x++, in += 4) {
+                            h->histogram[*in]++;
+                            if (im->bands == 2) {
+                                h->histogram[*(in + 3) + 256]++;
+                            } else {
+                                h->histogram[*(in + 1) + 256]++;
+                                h->histogram[*(in + 2) + 512]++;
+                                h->histogram[*(in + 3) + 768]++;
+                            }
                         }
                     }
                     ImagingSectionLeave(&cookie);