Fix custom icons not displaying (#7717)

* Fix custom icons not displaying

* Refactor

p/f.php

@@ -25,7 +25,9 @@ $ico = FAVICONS_DIR . $id . '.ico';
 $ico_mtime = @filemtime($ico) ?: 0;
 $txt_mtime = @filemtime($txt) ?: 0;
 
-if ($ico_mtime == false || $ico_mtime < $txt_mtime || ($ico_mtime < time() - (mt_rand(15, 20) * 86400))) {
+$is_custom_favicon = $ico_mtime != false && $txt_mtime == false;
+
+if (($ico_mtime == false || $ico_mtime < $txt_mtime || ($ico_mtime < time() - (mt_rand(15, 20) * 86400))) && !$is_custom_favicon) {
 	if ($txt_mtime == false) {
 		show_default_favicon(1800);
 		exit();