sequencediagram.org came to the rescue. I even have Lucidchart account. But their sequence diagram markup language is pretty limited in option. Even my earlier post was better to draw a sequence diagram if you are planning to write some text & just get it done with (Obviously Lucidchart can do a lot more things than drawing a sequence diagram from input text).
So feel free to try this new one out & check the syntax for different options & features.