Custom Private Message Button with Subject?

[BHall]

Calling all my html experts, devs, community hackers etc....is there a way to automagically populate a private message subject using a link/button?  For example, I have the following button...

<form action="/t5/notes/privatenotespage/tab/compose/note-to-user-id/41580" method="post"><button class="lia-button lia-button-primary" type="submit">Private Message Me</button></form>

...which would take you to the PM compose page...is there a way to insert a pre-selected/standard subject? In other words, we are trying to have a specific button/link auto-populate the PM subject, based on where the button is.

I know that we do this with Forum posts generated from our support site with the following url pattern:

https://community.virginmobileusa.com/t5/forums/postpage/choose-node/true?message-subject=abcdefg 

but "message-subject" does not appear to be a valid parameter for a <form> element in my first example.

What am I missing?

[TariqHussain]

Unlike forum post, you can not add message subject from URL. However, as a workaround you can get the subject value from URL and insert it to private message subject input using jQuery. 

[BHall]

Thanks @TariqHussain.

Any clues on how to do this in the context of a <form> or <button> ?

[TariqHussain]

@BHall - Create a component and add it to Notes Compose page. 

Freemarker 

<#assign subject = http.request.parameters.name.get("message.subject", "")?html />

jQuery

$(document).ready(function(){
  jQuery(".lia-form-subject-input.lia-form-type-text.lia-form-input-vertical").val("${subject}");
})

Once you will pass message.subject parameter with the subject, it will automatically be added to the subject input field. 

e.g https://community.lithium.com/t5/notes/composepage/note-to-user-id/53021?message.subject=Subject%20of%20message