How do I hide posts with a specific hashtag in Yammer?

I want to hide posts in the feed that have a #joined hashtag. I tried to create a GreaseMonkey script with jQuery in the past, but it couldn't detect any posts that have the #joined text.

Am I using the wrong library? A starting point, or an existing library/plug-in would be helpful.

OFF-TOPIC: At the moment, Yammer does not have any feature to hide posts with a specific hashtag, although it has a feature to follow a hashtag.

Solution

I know that this is a pretty old question but I too was trying to create a Chrome based Add-on that hides these #joined posts (or any post with a specific hashtag). I came across this blog https://you.stonybrook.edu/thebaron/2014/10/06/hiding-joined-yammer-posts-in-chrome/ where the author of the post has shared his work (https://gist.github.com/thicknrich/e4cc2871462a6850fe8c). This is a simple javascript and does the job.

//Script from https://gist.github.com/thicknrich/e4cc2871462a6850fe8c

//load jQuery based on this SO Post: 
//http://stackoverflow.com/questions/2246901/how-can-i-use-jquery-in-greasemonkey-scripts-in-google-chrome
// a function that loads jQuery and calls a callback function when jQuery has finished loading
function addJQuery(callback) {
  var script = document.createElement("script");
  script.setAttribute("src", "//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js");
  script.addEventListener('load', function() {
    var script = document.createElement("script");
    script.textContent = "window.jQ=jQuery.noConflict(true);(" + callback.toString() + ")();";
    document.body.appendChild(script);
  }, false);
  document.body.appendChild(script);
}

// the guts of this userscript
function main() {
  // Note, jQ replaces $ to avoid conflicts.

  setInterval(function() {
  //if a item thread contains #joined, hide it
  //check every 5 second. 
    jQ('.yj-thread-list-item:contains("#joined")').css("display", "none");
}, 5000);

}

// load jQuery and execute the main function
addJQuery(main);