diff --git a/thirdparty/sokol/sokol_gfx.h b/thirdparty/sokol/sokol_gfx.h
index bbeb80cd08..897257be8d 100644
--- a/thirdparty/sokol/sokol_gfx.h
+++ b/thirdparty/sokol/sokol_gfx.h
@@ -9490,8 +9490,7 @@ _SOKOL_PRIVATE void _sg_mtl_copy_image_content(const _sg_image_t* img, __unsafe_
             for (int slice_index = 0; slice_index < num_slices; slice_index++) {
                 const int mtl_slice_index = (img->cmn.type == SG_IMAGETYPE_CUBE) ? face_index : slice_index;
                 const int slice_offset = slice_index * bytes_per_slice;
-//                SOKOL_ASSERT((slice_offset + bytes_per_slice) <= (int)content->subimage[face_index][mip_index].size);
-                if (!((slice_offset + bytes_per_slice) <= (int)content->subimage[face_index][mip_index].size)) continue;
+                SOKOL_ASSERT((slice_offset + bytes_per_slice) <= (int)content->subimage[face_index][mip_index].size);
                 [mtl_tex replaceRegion:region
                     mipmapLevel:mip_index
                     slice:mtl_slice_index
diff --git a/vlib/stbi/stbi.v b/vlib/stbi/stbi.v
index 53b4331462..ddf8868962 100644
--- a/vlib/stbi/stbi.v
+++ b/vlib/stbi/stbi.v
@@ -39,8 +39,13 @@ pub fn load(path string) ?Image {
 		ext: ext
 		data: 0
 	}
-	flag := if ext == 'png' { C.STBI_rgb_alpha } else { 0 }
-	res.data = C.stbi_load(path.str, &res.width, &res.height, &res.nr_channels, flag)
+	// flag := if ext == 'png' { C.STBI_rgb_alpha } else { 0 }
+	desired_channels := if ext == 'png' { 4 } else { 0 }
+	res.data = C.stbi_load(path.str, &res.width, &res.height, &res.nr_channels, desired_channels)
+	if desired_channels == 4 && res.nr_channels == 3 {
+		// Fix an alpha png bug
+		res.nr_channels = 4
+	}
 	if isnil(res.data) {
 		return error('stbi image failed to load from "$path"')
 	}