assume default values if xdg dirs not set

.local/bin/statusbar/mailbox

@@ -13,7 +13,7 @@ case $BLOCK_BUTTON in
 - Middle click syncs mail" ;;
 esac
 
-unread="$(find $XDG_DATA_HOME/mail/*/INBOX/new/* -type f | wc -l 2>/dev/null)"
+unread="$(find ${XDG_DATA_HOME:$HOME/.local/share}/mail/*/INBOX/new/* -type f | wc -l 2>/dev/null)"
 
 icon="$(cat "/tmp/imapsyncicon_$USER")"