--- rxvt-unicode/src/perl/background	2022/04/22 17:02:39	1.105
+++ rxvt-unicode/src/perl/background	2022/11/29 08:48:22	1.109
@@ -1450,11 +1450,9 @@
 }
 
 # helper function, quote string as perl without allowing
-# any code execution or other shenanigans. does not
-# support binary NULs in string.
+# any code execution or other shenanigans.
 sub q0 {
-   (my $str = shift) =~ s/\x00//g; # make sure there really aren't any embedded NULs
-   "q\x00$str\x00"
+   "qq\x00\Q$_[0]\E\x00"
 }
 
 sub old_bg_expr {