diff --git a/bin/random_wallpaper b/bin/random_wallpaper
index 1fc68b6..5111ebd 100755
--- a/bin/random_wallpaper
+++ b/bin/random_wallpaper
@@ -9,7 +9,7 @@ minutes=15
 PROGRAM=`which feh`
 
 # Some tests
-if [[ "$XDG_SESSION_TYPE" -eq "wayland" ]]; then
+if [[ "${XDG_SESSION_TYPE}" == "wayland" ]]; then
   PROGRAM=`which swaymsg`
   if [ -z "${PROGRAM}" ]; then
     echo "This script needs the swaymsg program."