Keep this as a separate commit as this isn't because the files have changed. The filenames have changed due to cache busting of PNG and Webp images.
See #8729
        resized, err := image.Resize("123x")
        c.Assert(err, qt.IsNil)
        c.Assert(image.MediaType(), qt.Equals, media.WEBPType)
-       c.Assert(resized.RelPermalink(), qt.Equals, "/a/sunset_hu36ee0b61ba924719ad36da960c273f96_59826_123x0_resize_q68_h2_linear.webp")
+       c.Assert(resized.RelPermalink(), qt.Equals, "/a/sunset_hu36ee0b61ba924719ad36da960c273f96_59826_123x0_resize_q68_h2_linear_2.webp")
        c.Assert(resized.Width(), qt.Equals, 123)
 }
 
        resized, err := image.Resize("800x")
        c.Assert(err, qt.IsNil)
        c.Assert(resized.MediaType().Type(), qt.Equals, "image/png")
-       c.Assert(resized.RelPermalink(), qt.Equals, "/a/gohugoio_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_800x0_resize_linear_2.png")
+       c.Assert(resized.RelPermalink(), qt.Equals, "/a/gohugoio_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_800x0_resize_linear_3.png")
        c.Assert(resized.Width(), qt.Equals, 800)
 }
 
        resized, err := image.Resize("101x101")
        c.Assert(err, qt.IsNil)
        c.Assert(resized.MediaType().Type(), qt.Equals, "image/png")
-       c.Assert(resized.RelPermalink(), qt.Equals, "/a/sub/gohugoio2_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_101x101_resize_linear_2.png")
+       c.Assert(resized.RelPermalink(), qt.Equals, "/a/sub/gohugoio2_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_101x101_resize_linear_3.png")
        c.Assert(resized.Width(), qt.Equals, 101)
        c.Assert(resized.Exif(), qt.IsNil)
 
 
        resizedAgain, err := image.Resize("101x101")
        c.Assert(err, qt.IsNil)
-       c.Assert(resizedAgain.RelPermalink(), qt.Equals, "/a/sub/gohugoio2_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_101x101_resize_linear_2.png")
+       c.Assert(resizedAgain.RelPermalink(), qt.Equals, "/a/sub/gohugoio2_hu0e1b9e4a4be4d6f86c7b37b9ccce3fbc_73886_101x101_resize_linear_3.png")
        c.Assert(resizedAgain.Width(), qt.Equals, 101)
        assertImageFile(c, image.(specProvider).getSpec().BaseFs.PublishFs, publishedImageFilename, 101, 101)
 }
 
        // Add or increment if changes to an image format's processing requires
        // re-generation.
        imageFormatsVersions = map[Format]int{
-               PNG: 2, // Floyd Steinberg dithering
+               PNG:  3, // Fix transparency issue with 32 bit images.
+               WEBP: 2, // Fix transparency issue with 32 bit images.
        }
 
        // Increment to mark all processed images as stale. Only use when absolutely needed.
 
                resizedPublished1, err := img.Resize("40x40")
                c.Assert(err, qt.IsNil)
                c.Assert(resizedPublished1.Height(), qt.Equals, 40)
-               c.Assert(resizedPublished1.RelPermalink(), qt.Equals, "/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_40x40_resize_linear_2.png")
-               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_40x40_resize_linear_2.png", true)
+               c.Assert(resizedPublished1.RelPermalink(), qt.Equals, "/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_40x40_resize_linear_3.png")
+               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_40x40_resize_linear_3.png", true)
 
                // Permalink called.
                resizedPublished2, err := img.Resize("30x30")
                c.Assert(err, qt.IsNil)
                c.Assert(resizedPublished2.Height(), qt.Equals, 30)
-               c.Assert(resizedPublished2.Permalink(), qt.Equals, "https://example.com/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_30x30_resize_linear_2.png")
-               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_30x30_resize_linear_2.png", true)
+               c.Assert(resizedPublished2.Permalink(), qt.Equals, "https://example.com/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_30x30_resize_linear_3.png")
+               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_30x30_resize_linear_3.png", true)
 
                // Not published because none of RelPermalink or Permalink was called.
                resizedNotPublished, err := img.Resize("50x50")
                c.Assert(err, qt.IsNil)
                c.Assert(resizedNotPublished.Height(), qt.Equals, 50)
                // c.Assert(resized.RelPermalink(), qt.Equals, "/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_50x50_resize_linear_2.png")
-               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_50x50_resize_linear_2.png", false)
+               assertShouldExist(c, spec, "public/gopher.changed_hu2e827f5a78333ebc04166dd643235dea_1462_50x50_resize_linear_3.png", false)
 
                assertNoDuplicateWrites(c, spec)
        })