Correctly read woff2 bounds

src/SixLabors.Fonts/Tables/Woff/Woff2Utils.cs

@@ -237,7 +237,8 @@ internal static class Woff2Utils
         }
 
         // Read the bounding box stream.
-        int bitmapCount = (numGlyphs + 7) / 8;
+        reader.BaseStream.Position = bboxStreamOffset;
+        int bitmapCount = ((numGlyphs + 31) >> 5) << 2;
         byte[] boundsBitmap = ExpandBitmap(reader.ReadBytes(bitmapCount));
         for (ushort i = 0; i < numGlyphs; i++)
         {

tests/SixLabors.Fonts.Tests/Issues/Issues_375.cs

@@ -0,0 +1,30 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+namespace SixLabors.Fonts.Tests.Issues;
+public class Issues_375
+{
+    [Fact]
+    public void DiacriticsAreMeasuredCorrectly()
+    {
+        Font font = new FontCollection().Add(TestFonts.PermanentMarkerRegularFile).CreateFont(142);
+
+        TextOptions options = new(font);
+
+        FontRectangle bounds = TextMeasurer.MeasureBounds("È", options);
+        FontRectangle size = TextMeasurer.MeasureSize("È", options);
+        FontRectangle advance = TextMeasurer.MeasureAdvance("È", options);
+
+        Font fontWoff = new FontCollection().Add(TestFonts.PermanentMarkerRegularWoff2File).CreateFont(142);
+
+        TextOptions optionsWoff = new(fontWoff);
+
+        FontRectangle boundsWoff = TextMeasurer.MeasureBounds("È", optionsWoff);
+        FontRectangle sizeWoff = TextMeasurer.MeasureSize("È", optionsWoff);
+        FontRectangle advanceWoff = TextMeasurer.MeasureAdvance("È", optionsWoff);
+
+        Assert.Equal(bounds, boundsWoff);
+        Assert.Equal(size, sizeWoff);
+        Assert.Equal(advance, advanceWoff);
+    }
+}