How to access email body in inbox list using InboxSDK?

I am trying to make a chrome extension for gmail and am currently tinkering around with InboxSDK but I am unable to figure out how do I access email body from the inbox list itself(without opening the email) to add labels depending on the content.

I get the threadRowView object but I am unsure what to do after that to get more details of the mail. I think getElement() might be able to help somehow but I am unable to make sure how do I extract the mail from raw gmail DOM. https://inboxsdk.github.io/inboxsdk-docs/lists/

I am yet to find a way to do this directly only by using InboxSDK but there is a workaround which can help you get shorter descriptive text from the email which is seen on the inbox list.

InboxSDK.load('1.0', 'YOUR_APP_ID').then(function(sdk) {
  sdk.Lists.registerThreadRowViewHandler(function(threadRowView) {
    var threadElement = threadRowView.getElement();
    var descriptiveText = threadElement.textContent;
    // do something based on the text
  });
});

Documentation

I will update the answer if I am able to a better solution but I think one way to this properly should be using Official Gmail API and get the message using messageID.