Fixed fs sort pref key invalid bug

file_system.go

@@ -2444,7 +2444,7 @@ func system_fs_handleFolderSortModePreference(w http.ResponseWriter, r *http.Req
 
 	if opr == "" || opr == "get" {
 		sortMode := "default"
-		if sysdb.KeyExists("fs-sortpref", folder) {
+		if sysdb.KeyExists("fs-sortpref", userinfo.Username+"/"+folder) {
 			sysdb.Read("fs-sortpref", userinfo.Username+"/"+folder, &sortMode)
 		}