TaskRayProjectDocusignActionLanding.page

<apex:page standardController="TASKRAY__Project__c">
  <script src="/apex/dsfs__DocuSign_JavaScript" />
  <input class="btn" type="button" id="docusignActionLink" value="Send with DocuSign" />
  <script>
    var recordId = '{!TASKRAY__Project__c.Id}';
    var sendToDocuSign = function(){
      var url = "/apex/dsfs__DocuSign_CreateEnvelope?DSEID=0&SourceID="+recordId;
      var win = window.open(url, '_blank');
      win.focus();
    }
  
    var button = document.getElementById("docusignActionLink");
    button.addEventListener("click", sendToDocuSign);
  </script>
</apex:page>

TaskRayTaskDocusignActionLanding.page

<apex:page standardController="TASKRAY__Project_Task__c">
  <script src="/apex/dsfs__DocuSign_JavaScript" />
  <input class="btn" type="button" id="docusignActionLink" value="Send with DocuSign" />
  <script>
    var recordId = '{!TASKRAY__Project_Task__c.Id}';
    var sendToDocuSign = function(){
      var url = "/apex/dsfs__DocuSign_CreateEnvelope?DSEID=0&SourceID="+recordId;
      var win = window.open(url, '_blank');
      win.focus();
    }
  
    var button = document.getElementById("docusignActionLink");
    button.addEventListener("click", sendToDocuSign);
  </script>
</apex:page>