Made manifest unescapeName take care of all \NNN codes.

frontend/src/js/misc/wb-collection-manifest.js

@@ -142,7 +142,7 @@ class WBManifestReader {
   }
 
   unescapeName(name) {
-    return name.replace(/(\\\\|\\040)/g, (_, $1) => ($1 === '\\\\' ? '\\' : ' '));
+    return name.replace(/(\\\\|\\[0-9]{3})/g, (_, $1) => ($1 === '\\\\' ? '\\' : String.fromCharCode(parseInt($1.substr(1), 8))));
   }
 
   escapeName(name) {