diff --git a/.scripts/tools/opout b/.scripts/tools/opout
index 1fe3928..df34398 100755
--- a/.scripts/tools/opout
+++ b/.scripts/tools/opout
@@ -5,7 +5,7 @@
 basename="${1%.*}"
 
 case "$1" in
-	*.tex|*.md|*.rmd|*.ms|*.me) setsid zathura "$basename".pdf >/dev/null 2>&1 & ;;
+	*.tex|*.md|*.rmd|*.ms|*.me|*.mom) setsid "$READER" "$basename".pdf >/dev/null 2>&1 & ;;
 	*.html) setsid "$TRUEBROWSER" --new-window "$basename".html >/dev/null 2>&1 & ;;
 	*.sent) setsid sent "$1" >/dev/null 2>&1 & ;;
 esac