diff --git a/bin/update-default-backgrounds b/bin/update-default-backgrounds
index 55b2cb79..fe26bb18 100755
--- a/bin/update-default-backgrounds
+++ b/bin/update-default-backgrounds
@@ -16,6 +16,7 @@ ln -sfv ../../../backgrounds/kali/$DESKTOP_BACKGROUND.xml ${DESTDIR}wallpaper/gn
 ln -nsfv ../../../wallpapers/$kde_wallpaper/contents ${DESTDIR}wallpaper/contents
 
 sed -i "s/defaultWallpaperTheme=.*/defaultWallpaperTheme=${kde_wallpaper}/" share/plasma/desktoptheme/kali/metadata.desktop
+sed -i "s/defaultFileSuffix=.*/defaultFileSuffix=${DESKTOP_BACKGROUND_EXTENSION}/" share/plasma/desktoptheme/kali/metadata.desktop
 
 # default background symlink for XFCE
 mkdir -p share/backgrounds/kali-16x9
diff --git a/share/plasma/desktoptheme/kali/metadata.desktop b/share/plasma/desktoptheme/kali/metadata.desktop
index 140dd6c0..2c68ec4c 100644
--- a/share/plasma/desktoptheme/kali/metadata.desktop
+++ b/share/plasma/desktoptheme/kali/metadata.desktop
@@ -18,6 +18,7 @@ FallbackTheme=default
 
 [Wallpaper]
 defaultWallpaperTheme=KaliFerrofluid
+defaultFileSuffix=.jpg
 defaultWidth=3840
 defaultHeight=2160