[nautilus/gnome-42] css: Checkerboard background for thumbnails with transparent area

[António Fernandes <antoniof src gnome org>]

commit f4e9a9ececad296001f172dfb94393f3fc844728
Author: utkarshvg2401 <utkarshvg2401 gmail com>
Date:   Sun Apr 10 01:00:39 2022 +0530

    css: Checkerboard background for thumbnails with transparent area
    
    Currently, images with transparent backgrounds have their thumbnails
    displayed with a white background image, which causes a visibility
    issue for white images with no background in light mode.
    
    Hence, a checkerboard background is added to the thumbnails of these
    images, making them clearly visible.
    
    Close https://gitlab.gnome.org/GNOME/nautilus/-/issues/2211

 src/resources/Checkerboard.png       | Bin 0 -> 184 bytes
 src/resources/css/Adwaita.css        |   4 ++--
 src/resources/nautilus.gresource.xml |   1 +
 3 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/src/resources/Checkerboard.png b/src/resources/Checkerboard.png
new file mode 100644
index 000000000..3e43acd93
Binary files /dev/null and b/src/resources/Checkerboard.png differ
diff --git a/src/resources/css/Adwaita.css b/src/resources/css/Adwaita.css
index f38923d9d..435fd51b1 100644
--- a/src/resources/css/Adwaita.css
+++ b/src/resources/css/Adwaita.css
@@ -260,6 +260,6 @@ flowboxchild:selected image {
               0px 0px 0px 1px alpha(@borders, 0.5),
               0px 2px 0px 0px alpha(@borders, 0.5);
   border-radius: 2px;
-  /* Opaque background for thumbnails with transparent areas. */
-  background-color: #fafafa;
+  /* Background for thumbnails with transparent areas. */
+  background: url('/org/gnome/nautilus/Checkerboard.png') repeat;
 }
diff --git a/src/resources/nautilus.gresource.xml b/src/resources/nautilus.gresource.xml
index 9e129b669..eec94cbf2 100644
--- a/src/resources/nautilus.gresource.xml
+++ b/src/resources/nautilus.gresource.xml
@@ -32,5 +32,6 @@
     <file>css/Adwaita.css</file>
     <file>css/nautilus.css</file>
     <file>text-x-preview.png</file>
+    <file>Checkerboard.png</file>
   </gresource>
 </gresources>