YTSearchFilter.user.js

// ==UserScript==
// @name        YouTube Filter
// @namespace   sadEmoji
// @author	sadEmoji
// @description Filters YouTube Videos (only works on firefox)
// @include     https://www.youtube.com/results?search_query=*
// @version     1.2.3
// @grant       none
// @require 	https://code.jquery.com/jquery-2.1.4.min.js
// ==/UserScript==

vscript=document.createElement('script');
vscript.src='https://code.jquery.com/jquery-2.1.4.min.js';
vscript.type='text/javascript';
vscript.id='fuck';
document.getElementsByTagName('head')[0].appendChild(vscript);

setInterval(function(){filter()},1000);

function filter()
{
	//Enter the blocked words here
	blockedWords=["MrSuicideSheep","Justin Bieber"];
	totalResults=$(".yt-lockup-content").length;



	 $(".yt-lockup-content").each(function()
	{
		
		for(i=0;i<blockedWords.length;++i)
		{
			//alert($(this).text())
			
			if($(this).text().toUpperCase().contains(blockedWords[i].toUpperCase()))
			{
				//alert(a);
				$(this).parent().hide();
				//alert("yes");
				return;
			}
		}

	})

}